I won’t tell the student the answer to the math problem until he ____on it for more than an hour

, English, Math or Chinese

It seems that my friends don’t understand me.— Don’t worry. I’m sure you will _________ them ifyou are really friendly to them.

The traditional view is ________ we sleep because our brain is “programmed” to make us do so

In the time of social reform,people’s state of mind tends to with the rapid changes of society.