.You should take __________ measures to avoid danger when doing exercise.
I asked her ______ I should do to lose weight, and she told me to balance my diet.
— Do you know the old man ______ on the bench over there? — He is my grandfather.
If you don’t learn to think _____ you are young, you may never learn.
A new way of teaching _____ in the article can make learning easier.
My mother asked me where _____, and I told her that I was going to buy some food.