as和though引导让步状语从句倒装

　　1.表语的倒装：

　　一般直接将表语提前到句首，若表语是带不定冠词a / an的单数可数名词，倒装后，不定冠词a / an须被省略。如：

　　Fine as / though he looks, he is ill with some serious diseases.

　　Child as / though he is, he knows much about the society.

　　2. 原形动词的倒装：

　　A. 动词前面带有情态动词may, might, will, would, can, could等时，只将行为动词提到句首，而这些情态动词保留在原处。

　　B. 若动词前面没有情态动词时，应在动词原来的位置加上助动词do的适当形式。

　　C. 用于这一句型的动词一般是不及物动词，而不能是系动词或及物动词。如：

　　Swim as / though he can, he can’t swim so far. 尽管他会游泳，但是他游不得那么远。

　　Run as / though he did, he didn’t run fast enough to catch the bus. 虽然他跑，但是他跑得不够快而没有赶上汽车。

　　3.状语倒装：

　　In the classroom as / though he stays, he doesn’t read his texts. 尽管他呆在教室里，但他不读书。

　　Carefully as / though he worked, he made some mistakes. 尽管他工作很细心，但还是除了一些差错。