— The pet cat in your hand is very nice. Is it _____?
— Yes, but I’ll give it to my friend Lucy as ______ birthday present.

An old friend of my sister's always helps my brother and______ with ______English.

Mrs. Liu teaches ______ English. We like ______ class very much.

— Can I tell Peter about the news?
— No, I don't want anyone else to know it. You_____ keep it to yourself.

I'm feeling much better now, so you ______ call the doctor.

— _______ I have a ticket, please?
 — Sorry, sir. All the tickets were sold out ten minutes ago.

— Wow! You look different! You______ wear glasses.
 — Yes, I did. But now I am wearing contact lenses(隐形眼镜).

They ______ play football last Friday because Simon forgot to bring his football here.

Trees ______fight air pollution. They are natural air conditioners.

— Must I do the work today?
— No, you _______. You may do it tomorrow.