1. as if (though)引导的从句中（谓语形式和wish后从句相同），如：
　　He treated me as if (though) I were a child.
　　He acted as if nothing had happened.

2. 在It's (high/about) time that后的从句中，从句通常用一般过去时，表示"是...时候了"，如：
　　It's time you went to bed.

3. 在would rather/sooner that的从句中，从句通常用一般过去时，表示"宁愿"，如：
　　I would rather (sooner) that you started the work at once.

4. 用在含有without, but for, in the absence of等介词或介词短语的句中，表示"要不是"，
　句子谓语形式和wish后的从句相同，如：
　　Without (But for, In the absence of) the rain, we should have had a pleasant journey.