问题

There are several research centers in China ________ a certain disease called Bird Flu is being studied.

A:which
B:where
C:when
D:what

正确答案是：

同类题型

Do you like your teacher —____.

If you want to know the meaning of the word______, you’d better look it up in the dictionary.

下列单词的划线部分发音为[ ei ] 的是 ______ 。

Let’s _ tothe movies now.――That great.

The plan you came up with doesn’t sound very practical. It will become the of the attack.