A study shows that people living in non-smoking areas are less likely to ________the habit of smoking．                       

I ______what he said and I _______him.

However, at times this balance in nature is disturbed, _______ a number of possibly unforeseen effects.

3. Some parents are just too protective. They want to ______ their kids from every kind of danger, real or imagined.

Don’t be worried about his safety．______, he is an eighteen-year-old young man.