How did it______ that humans speak so many different languages?
| A．come out | B．come off | C．come about | D．come round |
The party last night was __________ big success and all the people present had __________ great fun.
| A．a;a |
| B．/;a |
| C．a;/ |
| D．/；/ |
The two sportsmen congratulated each other __________ winning the match by shaking hands.
| A．with |
| B．on |
| C．in |
| D．to |
The development of the city's industry __________ its environment pollution.
| A．has added up |
| B．has added to |
| C．has added up to |
| D．was added to |
He has worked __________ the maths problem for nearly an hour but he simply can't work it __________.
| A．on；at |
| B．on；out |
| C．at；up |
| D．for；out |
The energy Jenny Bowen has devoted in the past ten years __________ the orphans has been considered __________ of great help.
| A．to help ； being |
| B．to helping；to be |
| C．to help ； to be |
| D．helping; being |