They had bought a house there_______ they moved there.

问题描述:

They had bought a house there_______ they moved there.
A.before long B.long before C.long ago D.after

选B,因为前面是过去完成时,后面是过去时,所以前面的事应该先发生,
译为:他们早在搬来之前就在这买了一套房子