急阿!改同义句(关于条件状语从句的知识)5)You can't send a letter unless you kon
3个回答

5 You can send a letter if you know the address.

6 You can't go in unless you're a member.

You can go in if you're a member.(均可)

7 Don't write to them again unless they reply.

8 They will hold a sports meeting unless it rains tomorrow.

兄弟好好学啊 ,思考比较一下怎么变得,if变成unless得后面的否定变肯定.即为:

.如果.不怎么样.===> .除非.怎么样