Question

anumberof修饰的是可数名词还是不可数名词，还是都可以

Answer 1

答：修饰是可数名词
a number of 表示很多,大量,后跟可数名词的复数形式,be动词也用复数形式.用法与many相似.
若干；许多
several; many
· A number of boys have been absent some time during the term.
这学期有许多男学生有时候缺课。
· A number of my friends came to the party.
我的一些朋友参加了这次聚会。
· A number of people were seen strolling in the park.
我们可以看到许多人在公园里散步。
· I have a number of letters to write.
我有一些信要写。

但是请注意a number of和 the number of 的用法区别

1)a number of 是“许多”的意思，修饰可数名词复数或代词，谓语动词用复数。

①A number of students in our school enjoy listening to music.

我校许多学生喜欢听音乐。

②A large number of books have been stolen from the library.

图书馆里遗失了很多书。

2)the number of 是“的数目”的意思，修饰可数名词复数，谓语动词用单数

①The number of pages in this book is two hundred.

这本书的页数是二百。

②The number of books stolen from the library is large.

图书馆遗失的书很多。

希望以上回答对有帮助

Answer 2

a
number
of
意为：许多，后面接复数名词，谓语动词用复数。
eg.A
number
of
students
were
absent
from
the
meeting.
许多学生没有到会。