1 . By the time of his death in 1884, he ___________ (make) important discoveries. (所给词的适当形式填空)

2 . That was the last time that he ________ ________(talk) with his father face to face.
那是最后一次他和父亲面对面地谈话。

3 . By the time Mr Wang returned home from Beijing, his son’s wedding _______.

A．ended

B．has ended

C．had been ending

D．had ended

4 . ------You went to the“Bird’s Nest”last month, didn’t you？
------Yes. That was the second time I ________ to Beijing National Stadium.

A．have been	B．were
C．had been	D．would be