Rick____a lot about Chinese culture since he came to China．（ ）
| A． |
has learned |
B． |
will learn |
| C． |
learns |
D． |
learned |
What do you think of your hometown，Kate？
It ____ a lot．It's more beautiful than before．（ ）
| A． |
has changed |
B． |
changes |
| C． |
will change |
D． |
change |
There are ___ sharing bikes in many cities．So there will be ___ pollution．（ ）
| A． |
less and less； more and more |
| B． |
less and less； fewer and fewer |
| C． |
more and more； less and less |
| D． |
fewer and fewer； less and less |
Don't throw rubbish everywhere，please．Building a civilized（文明的）city is our duty．
_______．（ ）
| A． |
OK，I will |
B． |
You are joking |
| C． |
Take it easy |
D． |
Sorry，I won't |
I saw Susan in the library just now．
No，it __ be her．She went to Shanghai this morning．（ ）
| A． |
must |
B． |
can't |
C． |
may |
D． |
needn't |
You'll get good grades ___ you work hard．（ ）
| A． |
although |
B． |
so |
C． |
if |
D． |
unless |