they were very sad to hear the news 为什么不用to have heard the news

问题描述:

they were very sad to hear the news 为什么不用to have heard the news

这里的to hear the news作原因状语,说明他们是因为听到这个消息才难过,并且这个消息对他们而言挺意外英语里面不定式做原因状语就可以不看时态吗 那不定式做什么的时候要看呢只有出现完成意义时才看时态