Research shows that humans ______ from selfish to unselfish behavior when they are watched.
| A．tell | B．switch | C．range | D．distinguish |
This problem is _for us; therefore, we must take it into serious consideration．
| A．ready | B．familiar |
| C．suitable | D．vital |
China's first regional regulation on online sales issued in Hangzhou, which ishome to a number of China's e-commerce heavyweights such as Alibaba, will take _effect on May l．
| A．the; \ | B．\;an | C．\, \ | D．a; the |
—Sorry, I don't want to go．I'm afraid I can't dance well
—!It's just for fun
| A．Cheer up | B．Keep it up |
| C．Come on | D．Go right ahead |
—Do you know anything about British history?
—______________. I have no interest in it.
| A．Take it easy! | B．Please don’t bother. |
| C．It’s up to you. | D．No. It’s beyond me. |
Going out is __________good means of relaxation. Would you like to go to __________park with me in the afternoon?
| A．the ;the | B．the; a | C．a; the | D．不填；a |