3.一般用and连接的两个单词或短语做主语时候，谓语用复数，但是下面用and连接的主语表示一个概念，谓语用单数：

    law and order           法制             soap and water       肥皂水

    a cup and saucer        茶杯碟子         fork and knife       刀叉

    the needle and thread   针线             trial and error      反复尝试，不断摸索

    horse and carriage      马车             time and tide        岁月

    bread and butter        奶油面包         the ebb and flow     盛衰，潮涨潮落

    如： If law and order   ________  not preserved， neither the citizen nor his property is safe.

    A. is     B. are     C. was     d. were

    答案：A.

    4.表示学科和某些疾病名称的名词是复数形式，作主语时候谓语动词用单数形式

    Linguistics is a branch of study on human language.

    5.有些名词形式上是复数，意义上是单数，根据意义一致原则动词用单数

    The chaos was stopped by the police

    The news is a great encouragement to us

    A series of debates between the lectures was scheduled for the next weekend.

    6.用and 连接的成份表示一个单一概念时候，动词谓语用单数形式

    Bread and butter is our daily food

    Time and tide waits for no man

    二。 谓语用复数情况

    1. 由and， both …and， 连接的并列主语，和both ，a few， many ，several 等修饰语后面谓语动词通常用复数形式。

    Few people know he and I were classmates when we were at college.

    2.集体名词police， public， militia， cattle ，class ，youth后常用复数形式的动词

    The Chinese people are brave and hardworking

    The cattle are grazing in the sunshine

    3.当表示民族的词与冠词合用当主语，谓语动词用复数形式

    The Japanese were once very aggressive

    4.某些形容词前面加定冠词表示一类人，做主语时候，谓语动词用复数

    The rich are not always selfish

    5.不可数名词作主语，其前有表示数量的复数名词修饰时，谓语动词用复数

    Three million tons of coal were exported that year

    三。谓语动词可用单数，也可以用复数的情况

    1. 就近一致原则

    这种情况下，谓语动词使用单数还是复数取决于最靠近该动词的主语的单复数，存在这种情况的主要由以下几种可能：

    1） 由连词 either…or…； neither…nor…； whether… or…；not only…but （also） ；or 等连接的并列主语

    Neither money nor fame has influence on me

    Not only you but also he is wrong

    2） 在倒装结构中，谓语动词与后面的第一个主语一致

    Blocking the open-sided porch， framed by the enveloping fog， stands a tall grave-faced policeman.

    Just outside the ruins is a magnificent building surrounded by tall trees.

    Although a great number of houses in that area are still in need of repair， there has been improvement in the facili