No one has yet succeeded in explaining the ___ of how life began.
| A．cause | B．problem | C．reason | D．puzzle |
It was the first time she for her mother .
| A．cook | B．has cooked |
| C．had cooked | D．cooked |
—— Mr. Smith must be having a good rest in his home comfortably at present.
—— In fact, he back work, ignoring the doctor’s suggestion that he a good rest,.
| A．has come ；should take | B．came；take |
| C．comes；should take | D．is coming；takes |
The stress caused by rushing to work and being held up in traffic jams the outbursts of public transport rage.
| A．leading to; | B．devotes to ; | C．contributes to; | D．comes to |
Close neighbors are better than distant relatives. This is simple truth that the Chinese people got to know in ancient times.
| A．a; / | B．a;a | C．the; a | D．/; the |
China plans to a scholarship designed exclusively for students coming to study in the country from nations Beijing's initiatives to build a Silk Road Economic Belt and 21st Century Maritime Silk Road.
| A．put up ; involved in; |
| B．set up ; involved in; |
| C．set aside; absorbed in; |
| D．put up ; involving in; |