The second C919 large passenger plane its first flight at Shanghai Pudong International Airport on December 17th， 2017．（ ）
A．completesB．completed
C．has completedD．was completing
Which club do you prefer to join，the chess club_____the dancing club？（ ）
| A． |
so |
B． |
but |
C． |
or |
D． |
for |
﹣Tom，_____here to carry the luggage upstairs for me，will you？ ﹣All right．（ ）
| A． |
come |
B． |
came |
C． |
coming |
D． |
to come |
According to the traffic law，children under 12_____ride bicycles on the road．（ ）
| A． |
won't |
B． |
wouldn't |
C． |
needn't |
D． |
mustn't |
Doctors tell us_____our hands before and after every meal．（ ）
| A． |
wash |
B． |
washed |
C． |
washing |
D． |
to wash |
The engineers will keep_____the project with the manager of the company．（ ）
| A． |
discuss |
B． |
discussed |
C． |
discussing |
D． |
to discuss |