1.The astronauts could do lmost anything when they lived in the Tiangong-1.
2.It was in London that the 30th Olympic Games was been held.(这是一个明显的考查强调句型的句子)
3.There was a time when he was obsessed with comeputer games.
4.That was the first time for him to stand on the stage of CCTV.句型 that was the first time for sb to do sth.
5.I found that it was impossible for me to express what he wanted to say. found是短暂性动词,一般不用完成时,其次“做……是不可能的”是句型“it is/was impossible for sb to do sth”