根据句意和汉语注释,在答题卡标有题号的横线上,写出单词的正确形式:
My brother sleeps with the window open _______________ (除非) it’s really cold.
We went back to the highway after the fog had __________________ (消失).
There are _____________ (各种各样的) kinds of stationary for children to choose from.
The problems are still under ____________ (讨论). Please wait for the results.