问题
填空题
基本语法。
1. I haven't heard from him ______ he went to America.
2. He won't be here______he is invited.
3. He will not go to the cinema ______he is very busy.
4. We found the key ______she had left it.
5. We found the books two days ______he had gone away.
答案
1. since 2. unless 3. because 4. where 5. after