1、虛擬語氣用于“條件虛擬句”、“so that 和 in order that 引導(dǎo)的目的狀語從句（謂語動(dòng)詞前用情態(tài)動(dòng)詞 can/could 或 may/migh）” 以及表示 “個(gè)人態(tài)度的名詞從句”.
2、It is time that 就是表示個(gè)人態(tài)度的名詞從句,含義是 “我認(rèn)為早就該或本該做某事了,但是卻沒有做”.該句型中that 引導(dǎo)的是主語從句,從句中要求用與事實(shí)相反的虛擬語氣.對(duì)現(xiàn)在虛擬用過去時(shí)（be 一般用 were）,對(duì)過去虛擬用過去完成時(shí).如：
　　It is time that you got up. 你早就該起床了.（表明對(duì)現(xiàn)在“你”遲遲不起床的態(tài)度）
　　It was time that he had set out on time. 他當(dāng)時(shí)本該按時(shí)出發(fā)的.（表明“他”在過去沒有按時(shí)出發(fā)的態(tài)度）
3、time 可以用 high, due,right等形容詞修飾,強(qiáng)調(diào) “正是該做的時(shí)候”,或者用介詞短語about time 強(qiáng)調(diào) “差不多該做的時(shí)候”.
4、類似的這種特殊名詞從句有跟在 wish、had better、would rather 后的賓語從句,如：
　　I wish that you were with us.（但愿你和我們?cè)谝黄?要是你和我們?cè)谝黄鹁秃昧耍?br/>　　You had better that went out for a walk. （你要是出去散步該有多好）
　　We would rather that he had stayed at home yesterday. （我們寧肯他昨天呆在家里 ,那該多好）