什么时候to是介词?to作介词时怎么样一眼就能看出来,有技巧吗??还是只 ...答:be strange (common, new, familiar, peculiar, distinct, sensitive, immune, vulnerable, indispensable) toAir is indispensable to life.Aircrafts are vulnerable to interference caused by radiation.This injection will make you immune to infection.二:表示对比,比较1:以-ior结尾的形容词,后接介词to表示比较...