1 . Beijing successfully held the 2014 APEC meeting, _____ won high praise from the member countries.

A．what

B．that

C．which

D．who

2 . The death of his devoted son was a painful experience, ______ he had never fully recovered.

A．from which	B．from whom
C．with which	D．with whom

3 . Harry Potter has made reading popular again, ______ is why parents and teachers like the book, too．

A．that	B．who
C．which	D．what

4 . A huge amount of oil was spilt on the East Sea, the causes of ______ are still under investigation.

A．it

B．that

C．which

D．whom

5 . He suddenly fell ill, ______ prevented him from attending his friend’s wedding.

A．why

B．what

C．that

D．which

6 . Advertising can influence consumers' moods，_____ in turn，can influence consumers’reactions to products．

A．that

B．which

C．where

D．when