Better go to see your sick colleague right now, ______ you? 

—Didn't the robot have a rest?—_______. Because it never gets tired.

---______ have you been in class today?     ---For two hours.

 -- Peter, set down the result of the experiment, ______?-- Oh, yes, but I need to find my pen first.

—Excuse me, _____ is Dalian from Beijing ?—It’s about three hours by car.