It should be open now中为什么要加be

句子中为什么要加to be?----She turn out to be slim beauty now you should be careful.为什么要加be而不直接是you should careful. it isn't the way i hoped would be中后面为什么要加be it will be better为什么加Be? should be in good order 为什么加be be able to open it should it be accepted It should be noted it should be more7 请问We should learn to be grateful,为什么要加to be? It must be terrible to be grown up!这句话里为什么要加be呢? It's so late now that the bookstore can't be open .怎么转化成too.