as倒装句有以下几种句型：
1、名词（形容词）+as/though+主语+系动词；Child as/though he is, he knows a lot about physics.
2、副词+as/though+主语+动词；Fast as you read, you can’t finish the book in two days.
3、动词原形+宾语或状语+as/though+主语+助动词/情态动词；Try hard as he will, he never seems able to do the work satisfactorily.
4、分词短语+as/though+主语+be动词。Raining hard as it is, I’m going out for a walk.
