—— It is rather cold here. Shall we light a fire? —— No, we______because things are easy to catch fire.
The student couldn’t _________what the teacher was trying to explain.
It won’t be long before we _____________ a way to overcome the difficulties.
When the future, many people will imagine a life high-tech devices.
---Do you think he will do me a favor?---As far as I know, he is the last one ___ others. He ___ be prepared to give you a hand, though.
As we all know, every minute _____ full use of ____ our lessons will do good to us students.