is it in the room ____ we used to do experiments that the opening ceremony will be held?A.that B.which C.where D. on which为什么不选A选C？？
热心网友
本句的结构是强调句．It is... that...，强调地点；中间where引导的是定语从句，修饰the room．
热心网友
is it in the room（ where we used to do experiments ）that the opening ceremony will be held?是在我们做实验的那个房间举行开幕典礼吗？where对应的是in the room.
热心网友
从句不缺少宾语