【题目】They made up their mind that they______ a new house once Larry changed jobs.
A.bought
B.would buy
C.have bought
D.had bought

【答案】B
【解析】句意：他们打算只要Larry换了工作他们就买新房子。once引导的是条件状语从句，根据主句将来时从句一般现在时的用法可知，从句一般过去时，主句应是一般将来时的过去时。故答案选B。