2009-7-27 P,1
Unit 15
BASIC and C Language
Chapter Four
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
2009-7-27 P,2
@ Part 1 Notes to Text
1) BASIC was developed in the early 1960s at Dartmouth
College by John Keenly and Thomas Kurtz as a
teaching language,BASIC最早是由约翰．凯莫尼和汤姆斯库茨于二十世纪 60年代初在达特茅斯学院作为一种教学语言而开发的。
注释,达特茅斯学院成立于一七六九年的达特茅斯学院是美国第九所历史最悠久的学院。学生来自全美五十个州和全世界一百余个国家，其中亚裔学生占百分之十，黑人学生占百分之七，西裔学生占百分之五，白人学生占百分之七十五。 该学院实行一种叫“达特茅斯计划”的学制，一年分四期。学生可以任选三期在校学习。这就使得许多学生可以更灵活地安排自己在校或到外校，甚或外国去短期学习的时间。 这个学院的著名毕业生有编纂著名的,韦伯斯特大字典,的丹尼尔 ·韦伯斯特（ 1801），著名少儿读物丛书,苏丝博士,的作者戈色尔 ·苏丝（ 1925），美国前副总统尼尔森 ·洛克菲勒
（ 1930）及几任联邦部长。
BASIC and C Language
2009-7-27 P,3
2) BASIC was selected as the high-level Iangauge for such
systems due to its simplicity and,compactness” in
memory compared to other high-level languages,BASIC被选作这种系统的高级语言，是因为它比其它高级语言简单并“节省”
内存。
注释,介词短语 due to its simplicity and,compactness” in
memory用作原因状语；过去分次短语 compared to other high-
level languages是比较状语。
3) A timesharing system improved not only efficiency,but
also ease of using an interactive language— BASIC— that
would allow each user to type programs into a terminal
(similar to a personal computer) on whose screen the output
would be displayed immediately,分时系统的出现不但提高了工作效率．而且使 BASIC一类交互式语言使用起来简单 —— 即允许每位用户同时把程序输入计算机终端 〔 与微机类似 〕,而输出则立即显示在各自的屏幕上。
注释,注意 that引导的从句表结果；从意义上来分析 on whose
screen the output would be displayed immediately则是非限制性定语从句,whose指代 each user’ s。
2009-7-27 P,4
4) ANSI developed a standard BASIC,however,most microcomputer
systems use their own particular implementation of BASIC,ANSI推出了标准的 BASIC。但是，大多数微机系统对 BASIC有自己特殊的执行过程。
注释,ANSI=American National Standards Institute 美国国家标准协会。
5) C was developed by Dennis Ritchie as a systems programming
language for UNIX,C语言是由 Dennis Ritchie为 UNIX而开发的一种系统编程语言。
注释,UNIX是历史最悠久的通用操作系统。 1969年，美国贝尔实验室的
K.Thompson和 D.M.Ritchie在规模较小及较简单的分时操作系统 MULTICS
的基础上开发出 UNIX,当时是在 DEC的 PDP-7小型计算机上实现的,1970年正式投入运行。此后数年,UNIX一直是一个限于在 AT&T内部使用的操作系统。 1971年，发展出以 PDP-11/20汇编语言所写成的 V1版，包括最基本的文件系统和一些简单的软件，之后，又经历了一些改进。 Linux是一套免费使用和自由传播的类 Unix操作系统，它主要用于基于 Intel x86系列 CPU的计算机上。这个系统是由全世界各地的成千上万的程序员设计和实现的。其目的是建立不受任何商品化软件的版权制约的、全世界都能自由使用的 Unix兼容产品。
2009-7-27 P,5
6) PASCAL Pascal语言注释,Pascal是一种计算机通用的高级程序设计语言。它由瑞士 Niklaus Wirth教授于六十年代末设计并创立。在
Pascal问世以来的三十余年间，先后产生了适合于不同机型的各种各样版本。其中影响最大的莫过于 Turbo Pascal
系列软件。它是由美国 Borland公司设计、研制的一种适用于微机的 Pascal编译系统。该编译系统由 1983年推出
1.0版本发展到 1992年推出的 7.0版本，其版本不断更新，
而功能更趋完善
End
2009-7-27 P,6 End
1,acronym n,首字母简略词 11,lexically adv,词法上
2,simplicity n,简单,简易,12,obviate v,消除,排除
3,compactness n,体积小；紧密 (度 ) 13,identifier n,标识符
4,stem n,主干 14,monadic adj,一元的
5,timesharing adj,分时的 15,addict adj,二元的
6,terminal n,终端 16,composite adj,合成的,复合的
7,enhancement n,增强 17,integer n,整数
8,dialect n,方言 18,permissive adj,许可的
9,uniformity n,一致 19,modularization n,模块化
10.implementation n,执行
& Part 2 Word Study
2009-7-27 P,7
Task 1,Listening training
Dictation of some key words
Directions,You will hear some key words twice,most of which are taken from
the Word Study,Then finish the Crossword Puzzle,(See you book p,)
2,Dictation of some key expressions
Directions,You will hear some key expressions twice,most of which are
taken from this text,Then you are asked to complete the missing words.
@Part3 Practice on Text
1) microcomputer__________
2) the high-level____________
3) ______________versions
4) ____________of the hardware
5) composite______________
6) floating point____________
systems
Iangauge
different
capabilities
symbols
numbers
2009-7-27 P,8
Read and Reply
Directions:Students are required to read aloud the whole text after
the teacher,Then give short answers to the following questions:
Task 2,Read,Write and Translate
In the early 1960s at Dartmouth College.
largely because microcomputer technology has advanced at
a very rapid rate and the language has been changed to take
advantage of the capabilities of the hardware.
Underlined characters.
c) What are allowed in identifiers,which can make them
more understandable?
a) When and where was BASIC developed by John Keenly
and Thomas Kurtz as a teaching language?
b) Why do most microcomputer systems use their own
particular implementation of BASIC?
2009-7-27 P,9
( )1) C laguange largely remained a teaching language until
the introduction of microcomputer systems in the mid-1970s,
( )2) BASIC was selected as the high-level Iangauge for such
systems because of its complexity and abstrusity (深奥 ),
( )3) Some of the monadic and addict operators have
unexpected precedence,
( )4) Almost all computer and microcomputer manufacturers
have adopted BASIC．
( )5) Underlined characters are not allowed in identifiers,so
that it cannot make them more understandable..
Read and Judge
End
F
F
T
T
F
2009-7-27 P,10
Directions:Read the following short passage,Complete it by filling in the missing words.
A,compiled B,human-readable C,be divided D,directly E,into
F,though G,these ends H,low level I,based J,to use
Computer languages can 1)________into two groups,high level languages
and 2)________languages,High level languages are designed to be
easier3)________,more abstract,and more portable than low level
languages,Syntactically correct programs in some languages are then
4)________to low level language and executed by the computer,Most
modern software is written in a high level language,compiled into object
code,and then translated 5)________machine instructions.
Computer languages could also be grouped 6)________on other criteria,
Another distinction could be made between human-readable and non
7)________languages,Human-readable languages are designed to be used
8)________by humans to communicate with the computer,Non human-
readable languages,9)________they can often be partially understandable,
are designed to be more compact and easily processed,sacrificing
readability to meet 10)________.
Read and Complete
End
C
H
J
A
E
I
B
D
F
G
2009-7-27 P,11
1)那场大火的起因至今还是个谜。（ remain）
2)人生常被喻为蜡烛。 (compare to)
3)大多数交通事故都是由于高速开车而引起的。
（ due to）
4)他完全无视这一切,好像它们根本不存在似的。
(ignore)
5)我很开心，因为我昨晚制定出的计划决在今天的大会上获得了通过。 (adopt)
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
What caused that big fire has remained a mystery up to now.
Man's life is often compared to a candle.
Most of the accidents took place due to driving at high speed.
He completely ignored all these facts as though they never
existed.
I’ m very happy that the plan I made last night was
adopted at the meeting today.
2009-7-27 P,12
Programming Languages
A programming language is an artificial language that can be used
to control the behavior of a machine,particularly a computer,
Programming languages,like human languages,are defined
through the use of syntactic(句法的 ;语法的 )and semantic(语义的 )rules,to
determine structure and meaning respectively.
Programming languages are used to facilitate(使容易 )communication
about the task of organizing and manipulating information,and to
express algorithms(运算 )precisely,Some authors restrict(限制 ) the
term "programming language" to those languages that can express
all possible algorithms; sometimes the term "computer language"
is used for more limited artificial languages,
Thousands of different programming languages have been created,
and new languages are created every year.
&Part4 Extensive Reading
2009-7-27 P,13
A prominent purpose of programming languages is to provide
instructions to a computer,However,programming languages differ
from most other forms of human expression in that they require a
greater degree of precision and completeness,When using a natural
language to communicate with other people,human authors and
speakers can be ambiguous(含糊的 )and make small errors,and still
expect their intent to be understood,However,computers do exactly
what they are told to do,and cannot understand the code the
programmer "intended" to write,The combination of the language
definition,the program,and the program's inputs must fully specify
the external behavior that occurs when the program is executed.
Many languages have been designed from scratch(从零做起 ),altered to
meet new needs,combined with other languages,and eventually
fallen into disuse(废弃 ),Although there have been attempts to design
one
2009-7-27 P,14
"universal" computer language that serves all purposes,all of them
have failed to be accepted in this role,The need for diverse
computer languages arises from the diversity(差异,多样性 )of contexts
in which languages are used:
Programs range from tiny scripts written by individual hobbyists(爱好者 )to huge systems written by hundreds of programmers,
Programmers range in expertise from novices(新手 ) who need
simplicity above all else,to experts who may be comfortable with
considerable complexity,
Programs must balance speed,size,and simplicity on systems
ranging from microcontrollers to supercomputers,
Programs may be written once and not change for generations,or
they may undergo nearly constant modification,
Finally,programmers may simply differ in their tastes,they may be
accustomed to discussing problems and expressing them in a
particular language.
2009-7-27 P,15
One common trend in the development of programming
languages has been to add more ability to solve problems using
a higher level of abstraction(抽象概念 ),The earliest programming
languages were tied very closely to the underlying hardware of
the computer,As new programming languages have developed,
features have been added that let programmers express ideas
that are more removed from simple translation into underlying
hardware instructions,Because programmers are less tied to the
needs of the computer,their programs can do more computing
with less effort from the programmer,This lets them write more
programs in the same amount of time.
Natural language processors have been proposed as a way to
eliminate the need for a specialized language for programming,
However,this goal remains distant and its benefits are open to
debate,Edsger Dijkstra took the position that the use of a formal
language is essential to prevent the introduction of meaningless
constructs,and dismissed natural language programming as
"foolish." Alan Perlis was similarly dismissive of the idea.
End
2009-7-27 P,16
@Part5 Notes to Passage
1)Programming languages,like human languages,are defined
through the use of syntactic and semantic rules,to
determine structure and meaning respectively.程序设计语言就如人类语言一样，是通过语法和语义规则的定义来确定各自的数据结构和意义的。
注释,介词短语 through the use of syntactic and semantic rules
是方式状语；不定式短语 to determine structure and meaning
respectively用作目的状语。
2)Some authors restrict the term "programming language" to
those languages that can express all possible algorithms;
sometimes the term "computer language" is used for more
limited artificial languages,有些在程序作者将“程序设计语言”
这个术语限于那些能表达所有可能的运算法则；有时，术语“计算机语言”是更为有限的人工语言。
注释,注意该句中使用了动词短语 restrict sth,To sth.的句型； that
can express all possible algorithms是定语从句，修饰
languages。
2009-7-27 P,17 End
3)Howerver,programming languages differ from most other forms of
human expression in that they require a greater degree of
precision and completeness.可是，程序设计语言与大多少其它人类语言表达形式的不同之处就在于：程序设计语言需要更高的精确度和完整性。
注释,注意 differ from sth/sb,in that（与 … 不同的地方是 … ）的用法。
例如：
She differs from me in many ways,她在许多方面都和我不一样。
Chinese differs greatly from Japanese in pronunciation.
汉语发音跟日语大不相同。
4)Many languages have been designed from scratch,altered to meet
new needs,combined with other languages,and eventually fallen
into disuse,许多语言都是完全重新开始设计出来，再为满足某种需求而改变，然后与其它语言混合在一起，最终被废止不用。
注释,该句只有一个主谓结构，因此是简单句。其谓语部分是由四个并列的动词组成；介词短语 from scratch的意思是：“从零开始、从无到有、
白手起家”；动词短语 fall into disuse意为“废止不用”。例如：
Many words have fallen into disuse,有许多的词已经废止不用了。
2009-7-27 P,18
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
A programming language's surface form is known as its 1)________,
Most programming 2)_______________are purely textual; they use
sequences of text including words,3)___________,and punctuation,
much like written 4)________languages,On the other hand,there
are some programming languages which are more graphical
5)______________,using spatial relationships between symbols
6)_______________a program.
The syntax of a language describes the possible 7)_____________of
symbols that form a syntactically 8)_______________,The meaning
given to a combination of symbols 9)___________by semantics,
10)___________________________are textual,this article discusses
textual syntax.
@Part6 Practice on Passage
End
syntax
languages
numbers
natural
in nature
to specify
combinations
correct program
is handled
Since most languages
2009-7-27 P,19
End of this Unit
Unit 15
BASIC and C Language
Chapter Four
&Part4 Extensive Reading@ Part 1 Notes to Text
@Part5 Notes to Passage& Part 2 Word Study
@Part3 Practice on Text @Part6 Practice on Passage
2009-7-27 P,2
@ Part 1 Notes to Text
1) BASIC was developed in the early 1960s at Dartmouth
College by John Keenly and Thomas Kurtz as a
teaching language,BASIC最早是由约翰．凯莫尼和汤姆斯库茨于二十世纪 60年代初在达特茅斯学院作为一种教学语言而开发的。
注释,达特茅斯学院成立于一七六九年的达特茅斯学院是美国第九所历史最悠久的学院。学生来自全美五十个州和全世界一百余个国家，其中亚裔学生占百分之十，黑人学生占百分之七，西裔学生占百分之五，白人学生占百分之七十五。 该学院实行一种叫“达特茅斯计划”的学制，一年分四期。学生可以任选三期在校学习。这就使得许多学生可以更灵活地安排自己在校或到外校，甚或外国去短期学习的时间。 这个学院的著名毕业生有编纂著名的,韦伯斯特大字典,的丹尼尔 ·韦伯斯特（ 1801），著名少儿读物丛书,苏丝博士,的作者戈色尔 ·苏丝（ 1925），美国前副总统尼尔森 ·洛克菲勒
（ 1930）及几任联邦部长。
BASIC and C Language
2009-7-27 P,3
2) BASIC was selected as the high-level Iangauge for such
systems due to its simplicity and,compactness” in
memory compared to other high-level languages,BASIC被选作这种系统的高级语言，是因为它比其它高级语言简单并“节省”
内存。
注释,介词短语 due to its simplicity and,compactness” in
memory用作原因状语；过去分次短语 compared to other high-
level languages是比较状语。
3) A timesharing system improved not only efficiency,but
also ease of using an interactive language— BASIC— that
would allow each user to type programs into a terminal
(similar to a personal computer) on whose screen the output
would be displayed immediately,分时系统的出现不但提高了工作效率．而且使 BASIC一类交互式语言使用起来简单 —— 即允许每位用户同时把程序输入计算机终端 〔 与微机类似 〕,而输出则立即显示在各自的屏幕上。
注释,注意 that引导的从句表结果；从意义上来分析 on whose
screen the output would be displayed immediately则是非限制性定语从句,whose指代 each user’ s。
2009-7-27 P,4
4) ANSI developed a standard BASIC,however,most microcomputer
systems use their own particular implementation of BASIC,ANSI推出了标准的 BASIC。但是，大多数微机系统对 BASIC有自己特殊的执行过程。
注释,ANSI=American National Standards Institute 美国国家标准协会。
5) C was developed by Dennis Ritchie as a systems programming
language for UNIX,C语言是由 Dennis Ritchie为 UNIX而开发的一种系统编程语言。
注释,UNIX是历史最悠久的通用操作系统。 1969年，美国贝尔实验室的
K.Thompson和 D.M.Ritchie在规模较小及较简单的分时操作系统 MULTICS
的基础上开发出 UNIX,当时是在 DEC的 PDP-7小型计算机上实现的,1970年正式投入运行。此后数年,UNIX一直是一个限于在 AT&T内部使用的操作系统。 1971年，发展出以 PDP-11/20汇编语言所写成的 V1版，包括最基本的文件系统和一些简单的软件，之后，又经历了一些改进。 Linux是一套免费使用和自由传播的类 Unix操作系统，它主要用于基于 Intel x86系列 CPU的计算机上。这个系统是由全世界各地的成千上万的程序员设计和实现的。其目的是建立不受任何商品化软件的版权制约的、全世界都能自由使用的 Unix兼容产品。
2009-7-27 P,5
6) PASCAL Pascal语言注释,Pascal是一种计算机通用的高级程序设计语言。它由瑞士 Niklaus Wirth教授于六十年代末设计并创立。在
Pascal问世以来的三十余年间，先后产生了适合于不同机型的各种各样版本。其中影响最大的莫过于 Turbo Pascal
系列软件。它是由美国 Borland公司设计、研制的一种适用于微机的 Pascal编译系统。该编译系统由 1983年推出
1.0版本发展到 1992年推出的 7.0版本，其版本不断更新，
而功能更趋完善
End
2009-7-27 P,6 End
1,acronym n,首字母简略词 11,lexically adv,词法上
2,simplicity n,简单,简易,12,obviate v,消除,排除
3,compactness n,体积小；紧密 (度 ) 13,identifier n,标识符
4,stem n,主干 14,monadic adj,一元的
5,timesharing adj,分时的 15,addict adj,二元的
6,terminal n,终端 16,composite adj,合成的,复合的
7,enhancement n,增强 17,integer n,整数
8,dialect n,方言 18,permissive adj,许可的
9,uniformity n,一致 19,modularization n,模块化
10.implementation n,执行
& Part 2 Word Study
2009-7-27 P,7
Task 1,Listening training
Dictation of some key words
Directions,You will hear some key words twice,most of which are taken from
the Word Study,Then finish the Crossword Puzzle,(See you book p,)
2,Dictation of some key expressions
Directions,You will hear some key expressions twice,most of which are
taken from this text,Then you are asked to complete the missing words.
@Part3 Practice on Text
1) microcomputer__________
2) the high-level____________
3) ______________versions
4) ____________of the hardware
5) composite______________
6) floating point____________
systems
Iangauge
different
capabilities
symbols
numbers
2009-7-27 P,8
Read and Reply
Directions:Students are required to read aloud the whole text after
the teacher,Then give short answers to the following questions:
Task 2,Read,Write and Translate
In the early 1960s at Dartmouth College.
largely because microcomputer technology has advanced at
a very rapid rate and the language has been changed to take
advantage of the capabilities of the hardware.
Underlined characters.
c) What are allowed in identifiers,which can make them
more understandable?
a) When and where was BASIC developed by John Keenly
and Thomas Kurtz as a teaching language?
b) Why do most microcomputer systems use their own
particular implementation of BASIC?
2009-7-27 P,9
( )1) C laguange largely remained a teaching language until
the introduction of microcomputer systems in the mid-1970s,
( )2) BASIC was selected as the high-level Iangauge for such
systems because of its complexity and abstrusity (深奥 ),
( )3) Some of the monadic and addict operators have
unexpected precedence,
( )4) Almost all computer and microcomputer manufacturers
have adopted BASIC．
( )5) Underlined characters are not allowed in identifiers,so
that it cannot make them more understandable..
Read and Judge
End
F
F
T
T
F
2009-7-27 P,10
Directions:Read the following short passage,Complete it by filling in the missing words.
A,compiled B,human-readable C,be divided D,directly E,into
F,though G,these ends H,low level I,based J,to use
Computer languages can 1)________into two groups,high level languages
and 2)________languages,High level languages are designed to be
easier3)________,more abstract,and more portable than low level
languages,Syntactically correct programs in some languages are then
4)________to low level language and executed by the computer,Most
modern software is written in a high level language,compiled into object
code,and then translated 5)________machine instructions.
Computer languages could also be grouped 6)________on other criteria,
Another distinction could be made between human-readable and non
7)________languages,Human-readable languages are designed to be used
8)________by humans to communicate with the computer,Non human-
readable languages,9)________they can often be partially understandable,
are designed to be more compact and easily processed,sacrificing
readability to meet 10)________.
Read and Complete
End
C
H
J
A
E
I
B
D
F
G
2009-7-27 P,11
1)那场大火的起因至今还是个谜。（ remain）
2)人生常被喻为蜡烛。 (compare to)
3)大多数交通事故都是由于高速开车而引起的。
（ due to）
4)他完全无视这一切,好像它们根本不存在似的。
(ignore)
5)我很开心，因为我昨晚制定出的计划决在今天的大会上获得了通过。 (adopt)
Read and Translate
Directions:Put the following sentences into English,using the words or phrases given.
End
What caused that big fire has remained a mystery up to now.
Man's life is often compared to a candle.
Most of the accidents took place due to driving at high speed.
He completely ignored all these facts as though they never
existed.
I’ m very happy that the plan I made last night was
adopted at the meeting today.
2009-7-27 P,12
Programming Languages
A programming language is an artificial language that can be used
to control the behavior of a machine,particularly a computer,
Programming languages,like human languages,are defined
through the use of syntactic(句法的 ;语法的 )and semantic(语义的 )rules,to
determine structure and meaning respectively.
Programming languages are used to facilitate(使容易 )communication
about the task of organizing and manipulating information,and to
express algorithms(运算 )precisely,Some authors restrict(限制 ) the
term "programming language" to those languages that can express
all possible algorithms; sometimes the term "computer language"
is used for more limited artificial languages,
Thousands of different programming languages have been created,
and new languages are created every year.
&Part4 Extensive Reading
2009-7-27 P,13
A prominent purpose of programming languages is to provide
instructions to a computer,However,programming languages differ
from most other forms of human expression in that they require a
greater degree of precision and completeness,When using a natural
language to communicate with other people,human authors and
speakers can be ambiguous(含糊的 )and make small errors,and still
expect their intent to be understood,However,computers do exactly
what they are told to do,and cannot understand the code the
programmer "intended" to write,The combination of the language
definition,the program,and the program's inputs must fully specify
the external behavior that occurs when the program is executed.
Many languages have been designed from scratch(从零做起 ),altered to
meet new needs,combined with other languages,and eventually
fallen into disuse(废弃 ),Although there have been attempts to design
one
2009-7-27 P,14
"universal" computer language that serves all purposes,all of them
have failed to be accepted in this role,The need for diverse
computer languages arises from the diversity(差异,多样性 )of contexts
in which languages are used:
Programs range from tiny scripts written by individual hobbyists(爱好者 )to huge systems written by hundreds of programmers,
Programmers range in expertise from novices(新手 ) who need
simplicity above all else,to experts who may be comfortable with
considerable complexity,
Programs must balance speed,size,and simplicity on systems
ranging from microcontrollers to supercomputers,
Programs may be written once and not change for generations,or
they may undergo nearly constant modification,
Finally,programmers may simply differ in their tastes,they may be
accustomed to discussing problems and expressing them in a
particular language.
2009-7-27 P,15
One common trend in the development of programming
languages has been to add more ability to solve problems using
a higher level of abstraction(抽象概念 ),The earliest programming
languages were tied very closely to the underlying hardware of
the computer,As new programming languages have developed,
features have been added that let programmers express ideas
that are more removed from simple translation into underlying
hardware instructions,Because programmers are less tied to the
needs of the computer,their programs can do more computing
with less effort from the programmer,This lets them write more
programs in the same amount of time.
Natural language processors have been proposed as a way to
eliminate the need for a specialized language for programming,
However,this goal remains distant and its benefits are open to
debate,Edsger Dijkstra took the position that the use of a formal
language is essential to prevent the introduction of meaningless
constructs,and dismissed natural language programming as
"foolish." Alan Perlis was similarly dismissive of the idea.
End
2009-7-27 P,16
@Part5 Notes to Passage
1)Programming languages,like human languages,are defined
through the use of syntactic and semantic rules,to
determine structure and meaning respectively.程序设计语言就如人类语言一样，是通过语法和语义规则的定义来确定各自的数据结构和意义的。
注释,介词短语 through the use of syntactic and semantic rules
是方式状语；不定式短语 to determine structure and meaning
respectively用作目的状语。
2)Some authors restrict the term "programming language" to
those languages that can express all possible algorithms;
sometimes the term "computer language" is used for more
limited artificial languages,有些在程序作者将“程序设计语言”
这个术语限于那些能表达所有可能的运算法则；有时，术语“计算机语言”是更为有限的人工语言。
注释,注意该句中使用了动词短语 restrict sth,To sth.的句型； that
can express all possible algorithms是定语从句，修饰
languages。
2009-7-27 P,17 End
3)Howerver,programming languages differ from most other forms of
human expression in that they require a greater degree of
precision and completeness.可是，程序设计语言与大多少其它人类语言表达形式的不同之处就在于：程序设计语言需要更高的精确度和完整性。
注释,注意 differ from sth/sb,in that（与 … 不同的地方是 … ）的用法。
例如：
She differs from me in many ways,她在许多方面都和我不一样。
Chinese differs greatly from Japanese in pronunciation.
汉语发音跟日语大不相同。
4)Many languages have been designed from scratch,altered to meet
new needs,combined with other languages,and eventually fallen
into disuse,许多语言都是完全重新开始设计出来，再为满足某种需求而改变，然后与其它语言混合在一起，最终被废止不用。
注释,该句只有一个主谓结构，因此是简单句。其谓语部分是由四个并列的动词组成；介词短语 from scratch的意思是：“从零开始、从无到有、
白手起家”；动词短语 fall into disuse意为“废止不用”。例如：
Many words have fallen into disuse,有许多的词已经废止不用了。
2009-7-27 P,18
1.Listening Challenge
Spot Dictation
Directions,The following passage will be heard 3 times,During the second time,you
are required to put the missing words or phrases in the numbered blanks according to
what you hear,The third time is for you to check your answers,Now the passage
begins.
A programming language's surface form is known as its 1)________,
Most programming 2)_______________are purely textual; they use
sequences of text including words,3)___________,and punctuation,
much like written 4)________languages,On the other hand,there
are some programming languages which are more graphical
5)______________,using spatial relationships between symbols
6)_______________a program.
The syntax of a language describes the possible 7)_____________of
symbols that form a syntactically 8)_______________,The meaning
given to a combination of symbols 9)___________by semantics,
10)___________________________are textual,this article discusses
textual syntax.
@Part6 Practice on Passage
End
syntax
languages
numbers
natural
in nature
to specify
combinations
correct program
is handled
Since most languages
2009-7-27 P,19
End of this Unit
