高级医学英语阅读与写作Chapter 8 Mechanics of Writing
2012-07-20 22:01:48   来源：37度医学网   作者：  评论：0 点击：

                            I invited some happy old retired medical workers   .

Commas are used in Group a because the adjectives are descriptive ones in the same columns and can modify the noun independently. Commas are not used in Group b because they are not in the same columns but in different columns, some of them are determiners; some, descriptive; some, categorizing adjectives.
 
             
Setting off modifiers or parenthetical parts
 
A.   Setting off adverbial phrases and clauses, especially initial long ones, from main clauses. e.g.
 
              With these words, the general dismissed his officers.
              Upon arriving at a village, we went to visit the school for carpenters.
              Working in the hospital, we learned how to diagnose.
              To understand how your body works, let's see how it is built.
As time has gone by, the science of medicine has become divided into many different fields.
              Because he was ill, he didn't come to class.
 
When the initial elements are short and there is no danger of misreading, the comma is often optional. e.g.
 
              With these words the general dismissed his officers.
As time has gone bythe science of medicine has divided into many different fields.
 
B.   Setting off non-restrictive attributives, especially clauses and appositives. e.g.
             
              He is acquainted with Mary, who is now working.
Taxicabs, which are everywhere expensive, cost less in New York than elsewhere.
              People, old and young, all came out to greet the guests.
Comrade Chen, head of the English Department, is to give a report on English tonight.
 
       A restrictive attributive can't be set off by a comma, or the sentence radically changes or becomes nonsense. e.g.
 
              Taxicabs that are dirtyare illegal in some cities.
              Taxicabs, which are everywhere expensive, cost less here than elsewhere.
Shakespeare's last play, The Tempest, is optimistic and even sunny in mood.
              The play Macbethhas been studied for over three hundred years.
 
C.       Setting off sentence modifiers (parentheses).
 
Commas are used with expressions such as he said, she remarked, I believed, he replied, and I’m afraid . e.g.
 
“I'm making preparations for an operation,”he said, “on a patient who is ill with appendicitis.”
                     She replied, “It's all Greed to me.”
                     This is, I believe, all the news concerning the conference.
 
Commas are often used after connective adverbs such as accordingly, anyhow, besides, consequently, furthermore, hence, indeed, instead, likewise, meanwhile, moreover, nonetheless, nevertheless, otherwise, still, then, therefore, thus. e.g.
                                                                                                 
I don't like the new dictionary; besides, (The comma is optional) it's too expensive.
You must pack plenty of food for the journey. Likewise, (The comma is optional) you'll need warm clothes, so pack them too.
I've never been to China; therefore, (The comma is optional) I don't know much about it.
I've never been to China; I, therefore, don't know much about it.
                                                           ↑      ↑ 
                                                                optional     
 
D.   Commas are used to prevent misreading or to make an omission. e.g.
 
              In the reference section, books are kept which may be taken from the library.
? In the reference section books are kept which may be taken from the library.
 
              Beyond, the open fields sloped gently to the sea.
              ? Beyond the open fields sloped gently to the sea.
 
              While burning, cedar has a distinct and strong odor.
              ? While burning cedar has a distinct and strong odor.
 
              To err is human; to forgive, (The comma indicates the verb omitted ) divine.
 
E.    Other uses:
             

direct address	Bill, have you seen Mary?
yes, no	Yes, I do. (No, I don't.)
short interrogatives	You are a student, aren't you?
places (addresses)	My teacher's address is Portland StateUniversity, Portland,Oregon, 97207, U.S.A.
Time	She was born in December 31, 1970. (But no comma for '31 December 1970.)
modifiers like 'in fact, for example, on the other and unfortunate- ly, certainly, in one's opinion, ...	For instance, a physician is doctor of internal medicine. A Surgeon, on the other hand, is a doctor who specializes in surgery. In fact, most people think only of doctors and nurses when they think of a hospital.
absolute phrases (absolute constructions)	We followed the narrow paths silently but swiftly, one behind the other. He groaned and fell to the floor, blood streaming from his nose.

                                                                                                                                    
No occurrence of commas
 
       Commas are not used for the following conditions:
A.   Between subject and verb, between verb or verbal and complement, or between an adjective and the word it modifies. e.g.
 
              Not:
The girl from Shanghai,is not used to the weather here.  (inappropriate)
                     Sheadmitted, that she was not used to the weather here.(inappropriate)
                     She is a pretty, little, girl.                                       (inappropriate)
 
              But:
Mary, who is now working, is a very pretty little girl. (A non-restrictive modifier set off by two commas may be used between subject and verb.)
 
B.     Between two compound elements, or predicates compound elements such as verbs (verbal phrases), subjects, complements, or predicates connected by coordinate conjunctions. e.g.
 
              He came to tea and stayed to dinner.
(no comma between two compound verbs)
              The boy and the girl went for a walk.
(no comma between two compound subjects)
              They were poor but proud.     
(no comma between two compound complements)
              He never smokes or drinks.      (no comma between two compound verbs)
 
C.   No comma with a period, a question mark, an exclamation mark, or a dash. e.g.
 
“Did you get the job?” (no comma here) the roommate asked.      
“I'm a doctor,” (no comma here) he said.                               
“What a nice day!” (no comma here) she exclaimed.             
Everything in the universe — (no comma here) ourselves, our food, the atmosphere, the furthest corners of space — (no comma here) is made of chemicals.            
 
D.   No comma before an opening parenthesis but a possible comma after a closing parenthesis. e.g.
 
Libraries are classified by contents as general ones and special ones (including medical, scientific engineering, etc.)            
↑no comma
 
After reading his book (his textbook), he began to do the exercises the teacher had assigned him.         ↑a comma
 
2.    The Semicolon (;)
 
A semicolon is used between coordinate phrases and clauses not joined by coordinate conjunctions (and, but, or, nor, for, so, yet) and between coordinate elements with internal commas. It is between a comma and a period in value.
 
Separating coordinates
 
A.  Separating coordinate phrases and clauses not connected by coordinating conjunctions (and, but, or, nor, for, so, yet) but by logical connectors (however, therefore, then, in addition...). e.g.
 
Then the March Hare put the watch in the tea;took it out; looked at it again;and said again, “It was the best butter.”               (phrases)
       It's getting on;we'd better go home.                     (clauses)
              He said that it was so;however, I was mistaken.          (clauses)
A specialist from the museum arrived and asked to examine it; then the family became excited.
The painting was valuable; in fact, the museum offered them thousand dollars for it.
 
B.   Separating coordinate phrases and clauses which are long and have internal punctuation. e.g.
 
       Between clauses:
       One can't work all the time, surely; one has to have a little fun.
He is constantly late for work, and yet nothing is yet said to him; I don't know how he gets away with it.
 
       In a series of items:
The older farmer kept a variety of poultry: chickens, for eggs and Sunday dinners; turkeys, for very special meals; and peacocks, for their beauty.
 
No occurrence of the semicolon
 
A.   A semicolon is not used with coordinate conjunctions. e.g.
 
       Not:
                     The train slowed down; and the lights outside grew brighter.
       But:
                     The train slowed down and the lights outside grew brighter.
 
       Not:
He pushed the box very hard down the slope; butfriction gradually caused it to slow down.
       But:
He pushed the box very hard down the slope, but friction gradually caused it to slow down.
 
If other punctuation marks precede the coordinate conjunctions, the semicolon can be used before them. e.g.
 
When we started, the sky was clear; but before we had gone two li, it began to rain.   
 
B.   A semicolon is not used between elements which are not coordinate. e.g.
 
       Not:
                     When we started; the sky was clear.
       But:
                     When we started, the sky was clear.
 
       Not:
                     Before we got there; the operation had begun.
       But:
                     Before we got there, the operation had begun.