问题

They were afraid to complain about the noise ________ they didn’t want to make an enemy of their neighbors.

A:because
B:unless
C:though
D:when;

正确答案是：

同类题型

So difficult ____that no one could ___ a good solutionto it.

I can see some children _________ basketball in the playground now.

The government is working on designing a new app people could contact cleaners through it.– How unbelievable!

Excuse me. Could you tell me ______—There is a bank on the second floor.

makes this shop different is that it offers more personal services.