是主语从句。例如 ltisgoodthatwearegoingtoplayfootballnextMonday.(下周一我们去踢足球太好了。)这个句子的it从形式看是主语，实际上它只是代替后面t......

1、that作指示代词：That is my book.那是我的书。2、that作指示形容词：We havent found any solution to deal with that pro......