(4)as也可以引导让步状语从句。要用倒装。
Child as(though)he is, he knows a lot.
Much as I like it, I won’t buy.
Try as he would, he couldn’t lift the heavy box.
3、原因状语从句:because, for, as, since, now that
(1)表示不知道的原因时用because,即说话人认为听话人不知道,因此because从句是全句最重要的部分,通常它被置于主句之后。
You want to know why I’m leaving? I’m leaving because I’m full.
for虽然表示不知道的原因,但其语气较because要弱得多,是可说可不说的话,它只能置于主句之后,这时,for是并列连词。如果不是因果关系,而是对前面主句的内容加以解释或推断时,只能用for。如:It’s morning now, for the birds are singing.(很显然,鸟叫不可能是“现在已是早上”的原因。)
(2)表示已经知道的原因时用as或since,即某种原因在说话人看来已经很明显,或已为听话人所熟悉,因此它是句中不很重要的部分。since要比as正式一些,它们通常被置于语句之前,但有时却相反。
Seeing all of the children already seated, he said,“Since everyone is here, let’s start.”
(3)下列情况下只能使用because:
①在回答why的问句时;
②在用于强调句型时;
③被not所否定时。
4、地点状语从句:where, wherever
Make a mark wherever you have any questions.
We will go where the Party directs us.