2019年mpacc考试英语真题——连词645

{01}. I wrote to my parents once a week,____ I was too busy with my teaching work.

A.it

B.unless

C.when

D.as

解析： unless＝if...not。
本题选B。
{02}1. — Have you known each other for long?
— Not very long, ____ we started to work in the company.

A.after

B.before

C.when

D.since

解析：还原过后应为： We have known each other since we started to work in the company.
本题选D。