问题

When did you become a volunteer for the elderly——Two years ago. I ______ this group since then.

A:joined
B:took part in
C:have joined
D:have been in;

正确答案是：

同类题型

His book, which _______ last week, should be another best-seller.

We finish our lessons 3:30pm.

Much __ his surprise, the moment he went into the classroom, every one stood up clapping to congratulate him ___ winning the first prize.

下列加横线字的注音全都正确的一项是（）

They don’t seem __________who ________forhelp.