a (the) number of…作主语时谓语的数

a (the) number of…作主语时谓语的数
 
一、“the number +复数名词”作主语，谓语用单数。如：
The number of the students increased to 500. 学生人数增加到了500人。
The number of students absent is 6. 缺席的学生人数为6。http://yingyu.chazidian.com
The number of jobs is increasing. 工作的数目正在增加。
The number of chairs in the room is ten. 屋内椅子共有十把。
The number of the unemployed is still increasing. 失业的人还在增加。
The number of cars has greatly in creased. 轿车的数量大大地增加了。
The number of stamp-collectors is growing apace. 集邮者的人数在迅速增加。
And here are the main points of the news again. The pound has fallen against the dollar. The Prime Minister has said that the government’s economic policies are working. The number of unemployed has reached five million. There has been a fire... 下面把资讯要点再说一遍。英镑对美元的比价已经下跌。首相说政府的经济政策正在起作用。失业人数已经达到500万。发生了一场大火……
二、“a number of+复数名词”作主语，谓语用复数。如：
A number of people were injured. 不少人受了伤。
There were a number of swans on the lake. 湖上有好些天鹅。
There are a number of factors which we’re to consider. 有很多因素我们需要考虑。
A number of houses were burned down in the fire. 在火灾中烧掉了不少房子。
A large number ofpeople have come to see the exhibition. 许多人来看展览会。
A number of workers have recently left the company. 最近有很多工人辞掉了工作。
A number of veterans have retired and some are ready to. 很多老队员已退役，另一些也准备退役。
A number of people have tried to find the treasure, but they have all failed. 许多人都努力寻找宝藏，但是他们都失败了。