The young couple, who returned my lost wallet, left _______ I could ask for their names.
| A．while | B．before |
| C．after | D．since |
﹣Why do people like pop music？I hate it so much．
﹣______ it is not your style，that doesn't mean it is bad．（ ）
| A． |
Only if |
B． |
Even though |
| C． |
Now that |
D． |
In case |
The number of medical schools reached 18 in the early 1990s and ______ around that level ever since．（ ）
| A． |
are remaining |
B． |
have remained |
| C． |
is remaining |
D． |
has remained |
I never worried about my son while I was away because my mother ______ him．（ ）
| A． |
drank a toast to |
B． |
played a joke on |
| C． |
kept an eye on |
D． |
made an apology to |
According to Professor Johnson，we don't have to read the book if we don't want to，as it is ______．（ ）
| A． |
worthwhile |
B． |
necessary |
C． |
optional |
D． |
serious |
Dr．Rowan，______ secretary resigned two weeks ago，has had to do all his own typing．（ ）
| A． |
whose |
B． |
of whom |
C． |
of which |
D． |
which |