___ the international situation experiences great changes, China and the US have more common interests and shoulder more common responsibilities[ ]

Kerry isn’t working hard to __________ his wife andchildren, which in my opinion will __________ his marriage failure.

How long ____ she __ the man— Since last August．

Dr. Black is a professor of chemistry._______, he is a famous writer.

Isome courses at university，so I can’t work full time at the moment