I don’t know how ________ commas. 

---She hardly plays computer games every week ,_________? ---Yes . She is a hard-working girl .

There used to be a hospital , __________?

—You can speak Chinese, _______ you? —No. we can only speak English.

---Your 12-year-old son doesn’t know much about shopping online, ________ he? --- ___________, actually shopping online is popular with teenagers these days.