The atomic weight of oxygen is_____than ______of the hydrogen.
| A．15 times heavier; that |
| B．15 times heavier: those |
| C．16 times as heavier; that |
| D．16 times as heavy; those |
Misunderstanding may ______ if people fail to communicate with each other.
| A．raise | B．rise | C．arise | D．add up |
My friend Martin was seriously affected by a strange fever; _____ , he could neither eat nor sleep.
| A．after all | B．as a result | C．on the other hand | D．however |
Yao Ming, who ______ the Houston Rockets, is working hard to make his dream come true.
| A．joined | B．joined in | C．took part in | D．competed in |
Much attention should be paid _______ the wild animals as many of them are dying out.
| A．protect | B．to protect | C．protecting | D．to protecting |
It is not rare in _______ that people at the age of forty are going to _________university for further education.
| A．90s; the | B．the 90s ; / | C．90s; a | D．the 90s; the |