This is one of the largest bridges that______on this river.
A. is ever built
B. has ever been built
C. was ever built
D. has ever built
By the time you get there tomorrow, they_____for beijing.
A. will have left
B. are leaving
C. will leave
D. are to leave
I ______(write) a book at the moment.
The Chinese people are doing things on one ______(do)so far.
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