The Blacks ______ dinner when I knocked at the door.A. is having B. are having C. were having
-- Is this i-phone _________?--No, it isn’t. I am just thinking of buying________.
The heavy rain stopped the tourists________climbing down the hill.
This is such________useful book that I have learned a lot from it.
—Middle school students don’t know much about shopping online,______they?—__________ . It’s very popular with teenagers .A. do,No,they don’tB. do,Yes,they doC. don’t,No,they don’t
A Wechat(微信)is an invention ________can help people talk to friends,share photos,ideas and feelings freely .A、which B、who C、/