1.should have finished
析:should have done 应该做完某事(事实上却没有)
2.When was it
析:考察强调句型,还原成陈述语句就好理解了
It was when that his brother went to America.
3.His father has been suffering heart disease and hasn't recovered yet.
析:从“至今还没有”可以看出必须用现在完成时,而且前一句必须用现在完成进行时,表示患病这种状态一直持续到现在.
4.trust,according to
译:她知道她不得不相信父母,而且根据他们所说,这是很有必要的.