7. 如果有两个形容词一起修饰一个名词时，使用逗号分隔这两个形容词。如果这两个形容词中的第一个形容词是用来修饰第二个形容词的，而不是修饰后面的名词，就不要用逗号分隔这两个形容词。
Use a comma to separate two adjectives that modify the same noun, but do not use a comma if the first of two adjectives modifies the second adjective, but not the noun. In considering this choice, ask yourself whether the two adjectives can be reversed. If they can, as in the first example below, separate them with a comma. If they can not, as in the second example below, do not use a comma.
Incorrect: The only approach to the city was by a long old highway.
Correct: The only approach to the city was by a long, old highway.
Incorrect: The suspect drove a light, blue truck.
Correct: The suspect drove a light blue truck.
In the second example, use of a comma would be incorrect, since "light" modifies "blue," and is therefore not part of a series of commas that modify the word "truck." However, on the off chance that the writer intended to write that the truck was light in weight as well as blue in color, then the first use would be correct. Thus, you can change the meaning of a sentence -- sometimes inadvertently -- by your use of commas.
8. 不要用逗号来替代引导词that。
Do not use a comma to replace the word "that."
Incorrect: The court decided, there is no constitutional right to a second appeal, except by means of a habeas petition.
Correct: The court decided that there is no constitutional right to a second appeal, except by means of a habeas petition
Also Correct:
The court decided there is no constitutional right to a second appeal, except by means of a habeas petition.
In the second correct example, removing the word "that" from the sentence is acceptable because its absence does not confuse the reader. However, leave "that" in a sentence if removing it would create some doubt in the reader''s mind concerning what the writer meant to convey.
9.不要用逗号分隔一个句子的并列谓语，除非不加逗号会令人费解或是并列谓语的第二部分需要强调。
As a general rule, do not use a comma to separate the parts of a double predicate, unless the sentence would be confusing without it, or the second part of the double predicate requires special emphasis. A double predicate exists where the sentence has one subject and two verbs related to that subject. (Please read rule 10 of this section as well.)
Incorrect: The customer finished his meal, and paid the check.
Correct: The customer finished his meal and paid the check.
使用逗号分隔并列谓语来强调的例子：
Correct Use of Comma to Create Emphasis:
The defendant had been employed as a cashier for twenty years, and never once was accused of stealing money from the register.
In the preceding example, the writer creates a greater emphasis on the defendant''s innocence by setting off the second part of the double predicate with a comma. Without the comma, the second thought seems like an afterthought.
使用逗号分隔句子避免歧义的例子：
Correct Use of Comma to Avoid Confusion:
The judge ruled that suppression of the evidence was required because it had been obtained illegally, and ordered the defendant released from prison.
In this example, the writer avoids confusion by using a comma to introduce the second in the series of compound verbs; without the comma, one might not be sure whether the verb "ordered" related to the subject "it" or the subject "the judge." By contrast, in the sentence above about the restaurant customer, the comma is not needed, because it is a simple sentence.
10. 当用连词连接两个独立从句时，在连词前加逗号。连词包括"and," "but," "or," "nor," 和 "yet"。
When joining two independent clauses with a conjunction, place a comma before the conjunction. Conjunctions include the words "and," "but," "or," "nor," and "yet."
Incorrect: The customer ate every piece of the apple pie and the waitress brought another pie.
Correct: The customer ate every piece of the apple pie, and the waitress brought another pie.
In the incorrect example, the reader may at first think the customer ate the pie and the waitress. In the correct example, the comma before the conjunction tells the reader, "Stop, another independent clause with its own subject (the waitress) is about to begin."
11.通常，在which前面加逗号，但不要在that前面加逗号。虽然有的作者习惯于用which来引入限制性从句，传统用法是用that来引入限制性从句，用which来引入非限制性从句。在引入限制性从句时，在that前不要加逗号，在引入非限制性从句时，在which前一定要加逗号。
Generally, use a comma before "which" but not before "that." Although some writers use "which" to introduce a restrictive clause, the traditional practice is to use "that" to introduce a restrictive clause and "which" to introduce a nonrestrictive clause. When writing a restrictive clause, do not place a comma before "that." When writing a nonrestrictive clause, do place a comma before "which."
Correct Restrictive Use:
The store honored the complaints that were less than 60 days old.
Correct Nonrestrictive Use:
The store honored the complaints, which were less than 60 days old.
These sentences have different meanings as well as different punctuation. In the restrictive sentence, the store honored only those complaints less than 60 days old, but not those over 60 days old. In the nonrestrictive sentence, the store honored all the complaints, all of which were less than 60 days old.
12. 在引号内加入逗号，不要在引号外面加，不论逗号是否是其所引用的引语的组成部分。一般的规则是，逗号，句号总是放在引号内，而其他标点，如问号，冒号，分号和感叹号都应该放在引号外面，除非他们原来就是所引用的引语的组成部分。
Place commas inside, not outside, quotation marks. Follow this practice whether or not the comma is part of the original quotation. The general rule is that commas and periods should be inside the quotation marks at all times, while all other forms of punctuation, such as question marks, colons, semicolons, and exclamation points, should be outside the quotation marks, unless they were contained in the original quotation.
Incorrect: The court held that "physical injury is not a required element of a sexual harassment claim", and the plaintiff went on to win her case.
Correct: The court held that "physical injury is not a required element of a sexual harassment claim," and the plaintiff went on to win her case.
13. 用两个逗号来分隔日期和地点。表述详细日期（年月日）时，或详细的地理位置（如国家，州，城市）时，在最后的项目前后加两个逗号。
Use two commas when setting off dates and places. When using a full date (month, date, year) or multi-part geographical designation (such as city and state or city and country), use two commas around the last part of the designation.
Incorrect: On June 28, 1974 Judge Hayes took her seat on the Supreme Court.
Correct: On June 28, 1974, Judge Hayes took her seat on the Supreme Court.
However: In June 1974 Judge Hayes took her seat on the Supreme Court.
Incorrect: Laredo, Texas was host for the 1994 World Rodeo Championship.
Correct: Laredo, Texas, was host for the 1994 World Rodeo Championship.
Incorrect: We arrived in Tokyo, Japan for the meeting of the G-7 leaders.
Correct: We arrived in Tokyo, Japan, for the meeting of the G-7 leaders.
参考：从属从句和短语；限制性从句和非限制性从句
Cross References: Dependent Clauses and Phrases; Clauses -- Restrictive and Nonrestrictive |
