〔 错例 〕A cart and horse are seen coming to us .
〔 改正 〕改 are 为 is。
〔 归纳〕以下名词短语都可视作单数。a watch and chain 一块带链的表，a needle and thread 一套针线，a knife and fork 一副刀叉，a cup and saucer 一套碟子茶杯，a coat and tie 一件上衣带领带，bread and butter 奶油面包，aim and end 目的，truth and honesty 真诚，child care and education 对孩子的管教，time and tide 岁月，the long and short of it 总的意思,iron and steel 钢铁,law and order 治安,soup and salad 汤与凉拌菜 ,hard struggle and plain living 艰苦奋斗与生活简朴。
4. Mary a + 单数名词作主语时，谓语动词用单数。
〔 错例 〕Many a scientist have devoted their lives to science .
〔 改正 〕改have 为 has
〔 归纳 〕A . a great many , a good many 都需要接复数名词，作主语时，动词用复数。B . more than one + 名词作主语时，动词用单数。C. more than one 不接名词时，动词用单数或复数都可以。D.在 there be 结构里用单数或复数。如：There is ( 或 are ) more than one student in the classroom .
5. one and a half …与 a + 名词 + or two 作主语
〔 错例 〕One and a half cakes are left on the plate .
〔 改正 〕改 are 为 is 。
〔 归纳 〕one and half + 名词作主语习惯上视作单数，但名词需要用复数形式。One or two + 名词作主语时视作复数；而 a + 名词 + or two 作主语时却可视作单数或复数。如：
There are one or two things I want to tell you .
A word or two is ( 或 are ) needed here . 这儿还需要一两个词。
6 . ( together ) with + 名词不影响原来主语的人称和数。
〔 错例 〕Mr.Wang , together with his wife , have gone to Australia .
〔 改正 〕改 have 为 has。
〔 归纳 〕下列词语与名词连用均不影响原来主语的人称和数：as well as , along with , as much as , but , except , in company with , more than , no less than , like , rather than , plus 等。
7 . 数词 + 名词表示重量、长短、距离、钱数、分数、时间等作主语时，动词用单数。
〔 错例 〕Twenty years are too long for a man\'s life .
〔 改正 〕改 are 为 is。
〔 归纳 〕动词用单数是因为我们把这些复数名词看成一个整体。如：
Three hours is enough for him to perform the operation .
表示艰苦难熬的岁月、时日作主语时动词也可用复数。如：
The first fifty years are the hardest . 最初的五十年是最艰难的。
8 . A number of books 与 The number of books 作主语时应选用数不相同的动词。
〔 错例 〕The number of books are twenty-three .
〔 改正 〕改 are 为 is。
〔 归纳〕A . the number of…意思是“…的数目；……的号码”，作主语时，动词用单数；a number of…意思是“许多…”，作主语时，动词用复数。如：The number of the key is 207 .
B . the average of + 名词作主语时动词用单数：an average of + 名词作主语时动词用复数。如：
The average of letters received each week is 600 . 平均每周收到的信件是600件。
An average of 600 letters a week are received by the newspaper\'s office . 报馆每周平均收到600封信。
9.a basket of eggs 等作主语，动词用单数。
〔 错例 〕A basket of pears are not enough for them .
〔 改正 〕改 are 为 is。
〔 归纳 〕下面短语作主语时，动词也用单数：a basket of ( eggs ) 一篮 ( 鸡蛋 ) ，a cluster of ( grapes ) 一串 ( 葡萄 ) ， a pile of ( apples ) 一堆 ( 苹果 )， a team of ( football players ) 一队 ( 足球运动员 ) 。但 a group of ( students ) 作主语时，动词通常用复数。但：A group of girls are playing hide-and-seek .