用方框中所给单词的适当形式填空,每词仅用一次.
send cheap two do reason |
Can you tell me the __________ why you were late for school?
My pen pal _________ me a postcard from New York next week.
You can buy the jacket ____________ because they’re on sale.
Scientists are trying to make the robot ___________ the same things as we do.
Do you take exercise __________ a week?