The students in this school plant ______ trees every year.
The rich man __________ much food__________ the poor families during the hard time.
If Simon ________ hard, he _________better results in English.
I think math is not ________ science.
The old man has________ useful horse and horse can do a lot of things for him.
When he walks ______ my desk, he often knocks my books off the desk.