We are not happy中谓语动词是are还是are not(aren't)

We are not happy中谓语动词是are还是are not(aren't) you are not的缩写是you're not还是you aren't? are not always中能不能缩写成aren't always 英文：aren’t=are not 的汉语是? you are not a doctor ,aren't you 还是are you? we ( )come from japan we are chinese a.aren't b.don't c.not 我们是朋友,英文是we are friends,are we?还是we are friends,aren't we? Are you not 和Aren't you?什么区别 Aren't you a teacher?不可用are not? no you are not?no you aren't? 树上没有鸟There are not birds in the tree.还是There aren't any bird we are not