Question

一道初中英语选择题，在线等，急！！！

Is this the room _____ he used as his first laboratory.
A.who B.that C.the one D.in which

Answer 1

B
He used the room as his first laboratory.
that/which 可代替the room，但是这句话不用加介词in
the one用于表特指，但是room前面的the已经可以表示特指了，所以不是the one，如果room前面没有the，则用the one，即Is this room the one he used as his first laboratory？
who只能指代人，不说了

Answer 2

选B
这里的that(填which也可以)做宾语。
指代的是his first laboratory

Answer 3

B!宾语从句.指代关系!

Answer 4

C

Answer 5

b

Answer 6

B吧