Many people do not realize the importance of health __________ they have fallen ill.
This is the beautiful park ______is near our school.
--- What shall we do this Sunday? --- Why ______to the Science Museum?
Tell her ______the teacher and _______ the window.
-- Could I clean the room for you ? --- No, thank you. I ________it myself.
Mr. Yang teaches ______math and is very strict with us.