1.关于it is important that...后使用虚拟语气的疑问：

（1）是否it was important that...也要使用虚拟语气？

（2）如果it is important that...中that句子是发生在过去的事情呢？如：it is important that he told the truth.句中正确与否？it was important that he told the truth.呢？

2.关于it is strange/ natural/ a pity that中使用虚拟语气的问题：

（1）it is natural that you should forget it.和 it is natural that you should have forget it.两个句子意思一样吗？是否都表示对已发生的事情的强烈感情色彩？

（2）it is natural that...中使用虚拟语气时表达的强烈感情色彩和natural本身的意思不矛盾吗，“竟然”和“自然，正常”。

（3）若要表达“你（以后）忘记它是正常的”是否就需要用陈述语气：It is natural that you forget will it (someday in the future).