定语从句中,as的用法,哪位大侠能总结一下不?答:as的这种用法常见于以下这些结构:as we can see, as can be seen, as we know, as is(well) known, as may be imagined, as often happens, as has been said before, as was mentioned above, as is often the case, as/indeed it is…例:As is well known,great changes have ...