﹣Jim，are these your keys？（ ）
﹣____．They're hers．
| A． |
Yes，it is |
B． |
No，it isn't |
| C． |
Yes，they are |
D． |
No，they aren't |
Dirty air and water are harmful． They ____ kill plants， and even people．（ ）
A．canB．can'tC．shouldD．shouldn't
My father ____ in a panda protection center for 10 years， so he knows a lot about panda．（ ）
A．was workingB．is working
C．has workedD．will work
____ smart the driverless car is! I really want to have one．（ ）
A．WhatB．What aC．What anD．How
A mobile phone with 5G can send videos much ____ than the one with 4G．（ ）
A．fastB．faster
C．fastestD．the fastest
It is said that one Greater Bay Area university ____ in Guangdong in the future．（ ）
A．will be builtB．build
C．will buildD．is built