规则1、 (来源：英语麦当劳－英语学习门户 http://www.EnglishCN.com)
In formal writing, one should not use abbreviations, except as indicated in rules 2, 3, and 4 below.
Incorrect: The U.S. Supreme Court held that the defendant's rights had been violated.
Correct: The United States Supreme Court held that the defendant's rights had been violated.
Incorrect: Professor Jonas mentioned several cities that have domestic-partnership ordinances, e.g., New York and San Francisco.
Correct: Professor Jonas mentioned several cities that have domestic-partnership ordinances, including New York and San Francisco.
Incorrect: The Court announced its decision in the case on Oct. 12, 1994.
Correct: The Court announced its decision in the case on October 12, 1994.
When an abbreviation has become so common that it has supplanted the full name in common usage, one may use the abbreviation; however, one should do so without the use of periods.
Incorrect: The N.A.A.C.P. was the subject of a profile on C.B.S. last week.
Correct: The NAACP was the subject of a profile on CBS last week.
（注： NAACP abbr.National Association for the Advancement of Colored People (美国)全国有色人种协进会，CBS abbr. （美国）哥伦比亚广播公司(Columbia Broadcasting System)）
However: The defendant in the case is R.J. Reynolds Industries, Inc.
Notice that in the preceding example, the points after "R" and "J" should be left in, because the meaning of the abbreviation is not sufficiently well known to most readers. Ordinarily, one would replace such an abbreviation with the full terms; however, one can not do so in this case because the legal corporate name involved includes the abbreviation.
When writing legal citations, always use the abbreviations required by the Bluebook. However, when referring to a court in text, do not abbreviate. For example:
Incorrect: The Ill. Supreme Court required the return of the child to his birth mother. Smithson v. Bettaglia, 59 Illinois 2d 73, 180 Northeast Reporter 2d 754 (1994).
Correct: The Illinois Supreme Court required the return of the child to his birth mother. Smithson v. Bettaglia, 59 Ill. 2d 73, 180 N.E.2d 754 (1994).
当行文中涉及的公司在其注册名称中含有一个或多个缩写时，如 R.J. Reynolds Industries, Inc.，应当保留缩写；不要把缩写所代表的全称全部拼出，除非公司的注册名称中已经全部拼出，如Exxon Shipping Company。这条规则适用于所有的公司名称中，包括Co.， Corp.， Inc.和 Ltd.。
When referring to a corporate entity that has one or more abbreviations as part of its legal name, such as R.J. Reynolds Industries, Inc., leave the abbreviations in the name. Do not spell out the abbreviation unless the corporation itself spells it out, which some do (for example, Exxon Shipping Company). This rule applies to all of the various forms of corporate designations, including Co., Corp., Inc., and Ltd.
Incorrect: McDermott International, Incorporated
Correct: McDermott International, Inc.
在四种情形下使用或不使用缩略符容易引起混淆，分别是（1）复数词（2）单数所有格（3）复数所有格和（4）it's和its的缩写形式（Contractions，see cross reference hereunder）与所有格。是否使用所有格，要先问问自己是否涉及领有关系。如果是领有关系，名词或带词就要采取所有格。
规则1、Plain plural words do not require the use of an apostrophe. For example:
Incorrect: The lawyer's could generally be found after hours at the Hanover Street Bar and Grill. (The apostrophe here incorrectly indicates a singular possessive.)
Incorrect: The lawyers' could generally be found after hours at the Hanover Street Bar and Grill. (The apostrophe here incorrectly indicates a plural possessive.)
Correct: The lawyers could generally be found after hours at the Hanover Street Bar and Grill. (The lack of an apostrophe here correctly indicates a plural, nonpossessive term.)
规则2、In singular possessive terms, place the apostrophe before the "s." This will indicate ownership by one person or thing. For example: