—Did you go to Jack’s birthday party? —No, I _______. 

—Mr Wang’s never been to Canada, has he?— ______. He went there on business last week.

一Middle school students don’t know much about shopping online, _______ they?一 _______. It’s very popu]ar with teenagers.

----She didn’t come to school yesterday, did she? ---- ___________, though she was not feeling very well.

--- There is little water left in the bottle, ______? --- No, we need to buy some more before we run out of it.