The young mother won't leave her baby _______ she is sure that he has already been asleep．（ ）
A．unlessB．becauseC．ifD．since
Hi，Joan! I won the men's 100﹣metre race yesterday!
That's wonderful news．（ ）
| A． |
Never mind． |
B． |
You are welcome． |
| C． |
Congratulations! |
D． |
That's all right． |
The book is excellent．Could you tell me ？（ ）
| A． |
where did you buy it |
B． |
where you bought it |
| C． |
where do you buy it |
D． |
where you buy it |
You always be careful with electricity for safety．（ ）
| A． |
must |
B． |
can |
C． |
mustn't |
D． |
can't |
A hanfu show in Museum of History next week．（ ）
| A． |
is held |
B． |
was held |
| C． |
will be held |
D． |
has been held |
When we succeeded in reaching the top of Mount Tai，we felt proud of_______ （ ）
| A． |
we |
B． |
us |
C． |
our |
D． |
ourselves |