They do eye exercises twice a day , so ____of them ____glasses.
Our Earth will be ________ if we go on cutting down millions of trees every year.
Trees provide food and shelter and make us ______ comfortable.
Trees make our city more beautiful and ________ noisy, do you think so?
Three trees can do the job of 15air-conditioners _________ almost all day.
He gave me clothes _____ food.