333 aswhenwhile意为although(尽管),

but(但是),seeing that(鉴于)

  

A 只有在形容词+as+主语+to beto seemto appear这一结构中,as才意为thoughalthough(尽管):

Tired as he was he offered to carry her.相当于:

Though he was tired he offered to carry her

尽管他很累了,他还主动提出要背着她。

Strong as he washe couldnt lift it

尽管他力气很大,他仍提不起这个东西。

B while可意为but,用于表示强调对比:

At seameanson a ship’,whileat the seameansat the seaside’.

At sea”意为“在船上”,而“at the sea”意为“在海滩上”。

Some people waste food while others havent enough

一些人糟踏食物而另一些人却食不果腹。

while可以意为although,这时常放在句首:

While I sympathize with your point of view I cannot accept it

尽管我认同你的观点,但我不能接受它。

C when可以意为seeing thatalthough(鉴于)。因此它同while 很相似,但主要用于引导使另一个动作显得不合理的陈述句。

它常用在一个问句里,但不是一定如此:

How can you expect your children to be truthful when you yourself tell lies

你自己都在撒谎,怎么能指望你的孩子们诚实?

Its not fair to expect her to do all the cooking when she has had no training or experience

她没有受过烹调方面的训练,也没有这方面的经验,让她把做饭的事全部承担下来是不公平的。

D 请务必不要搞混whenif的用法。

When he comes(等他来了)意为我们肯定他会来的。If he comes(如果他来了)意为我们不能肯定他是否会来。

(关于if用于条件句,参见第二十一章。)