Question

4. Mr Li bought a new house,but        before he could move in. (need)

李先生买了新房子，伹是在他搬进去之前需要做很多工作。

Answer 1

4. it needed a lot of work/a lot of work needed to be done题干中有并列连词but ,表明这是一个并列句，因此，不可用which来引导一个非限制性定语从句。