Our teacher, Mr. Zhang, has taught English ________ ten years ago.
________ I know, Tom is the best student in his school.
--________do you learn computer programming? --________asking my uncle for help.
There are three ________ and two ________ in the meeting room.
The number of the students in our class ________ forty-eight. A number of them ________ to school on foot.
A lot of trees ________ around here every year, and we can enjoy fresher air now.