1 . She gave another piece of advice,         I think is of great help to the research work.

A．that

B．who

C．what

D．which

2 . Pumpkins are believed to have originated in North America, _______ seeds from related plants have been found dating back to 7,000 B.C.

A．as

B．which

C．where

D．whose

3 . ________ was once predicted by a famous scientist, in another twenty years, AI robots would completely ________ humans as workers.

A．It; take place of

B．As; take the place of

C．It; in the place of

D．As; in place of

4 . Mr Zhou, ________native language was Chinese, could read and write several foreign languages.

A．whose

B．his

C．which

D．that

5 . David donated a large sum of money and some necessities to the charity, _________he received a heartfelt letter of thanks from the organization.

A．for which

B．with whom

C．about whose

D．in where

6 . A more recent work of his is the huge Floating Fish, _____ was set among the beautiful landscape of Wuzhen West Scenic Zone.

A．What

B．that

C．who

D．which

7 . On the wall hung a picture, _________ color is blue.

A．whose

B．of which

C．which

D．its

8 . Mozart composed many famous operas during his final years, ______ were largely unfinished when he died.

A．that

B．when

C．which

D．for which

9 . Laughter is the best medicine, _________ means keeping a good mood is helpful to our health.

A．what

B．which

C．that

D．it

10 . This aspect will be discussed further by Crane in the next lecture, ________ I mentioned just now.

A．whom

B．why

C．that

D．when