a number of

a number of许多，大量的

【例句】

◆ A number of problems have arisen．已经出现了许多问题。

【辨析】the number of和a number of       

the number of意为”……的数量或数目”，后接可数名词复数，作主语时谓语动词用单数。

a number of后跟可数名词复数，作主语时谓语动词用复数形式。如：Today the number of people learning English in China is increasing rapidly．当今中国学英语的人数正迅速增加。（人教版，必修①，Unit 2）

A number of students took part in the sports meet．许多学生参加了这次运动会。

【联想】表示”许多，大量”的短语有三种类型：可以修饰可数名词的有a good/great/large number of        只能修饰不可数名词的有a great/good deal of, a large amount of  既可修饰可数名词又可修饰不可数名词的有a lot of, lots of, plenty of, a quantity of, quantities of

【微测】  

1．He noticed that Toodles had been reading____ unusually high number of adventure books lately...                                                                            [an]

2. The website asks visitors to join in the movement to reduce____ number of illiterate（不识字的）people in the world.                                                              [the]