选择题Where is the key ____ fits this lock?A.which B.who C.how D.what选哪个?为什么?

问题描述:

选择题Where is the key ____ fits this lock?
A.which B.who C.how D.what
选哪个?为什么?

which
这是定语从句,“fits this lock”做“key”的定语,意为:那把适合这个锁的钥匙在哪里?