同意刘老师的分析。又如：

He is such a bear that nobody likes him. 他是一个粗鲁无礼的人,没有人喜欢他。《现代英汉综合大词典》

▲如果名词前有形容词构成“such a + adj.+名词”还可转换为“so + adj. + a + 名词”如：

She is such a good dancer. = She is so good a dancer.

I'm such a pushover.

我真是太好欺负了。

pushover 在句中作表语成分

(1)易被劝服的人

He is a tough negotiator. We did not expect to find him a pushover and he has not been one. 

他是个难对付的谈判者。我们没指望说服他，而且也没说服他。

(2)容易做的工作；易如反掌的事；唾手可得的东西

You might think Hungarian a pushover to learn. It is not. 

你可能认为匈牙利语很容易学。其实不然。

注意冠词的位置

不定冠词用于固定结构quite/half/rather/many/what/such a (an)+名词或so/too/how+形容词+a(an)+名词中，表示程度、数量或感叹等.

A:quite/half/rather/many/what/such a (an)+名词

It takes half an hour to get there. 到那里需要半小时。
He's quite a famous artist. 他是个很有名的艺术家。
Many a man would welcome such an opportunity.

许多人会很高兴有这样一个机会。
What a fool he is! 他多傻啊！
It's too difficult a problem for him.对他来说，这是一个太难的问题。

I have a number of sponsored students.
Mary has a lot of money.

Tom is rather a fool.
I think Chinese is quite a useful language.
Many a student has asked that question.
The visitor left half an hour ago.
What a fine day it is!
How can you say such a thing?

B:so/too/how+形容词+a(an)+名词

We have not had so hot a day before.
Susan is as clever a girl as Anna.
That is too difficult a book for beginners.
No one knew how serious a problem it was until later.