There are certain _______when you have to interrupt people who are in the middle of doing something.
If his parents are convinced ____the fact that his son always focuses his mind his study.
I will go to the science palace to morrow ____ it doesn’t rain heavily.
____ the rain, he insisted, the football game can not be cancelled.
Speaking of Tom, there are several things that are not easy to ____ ,say, his dishonesty.
—Have you get accustomed to the weather here, Jane? —Yes. But I don’t like______when it is wet.