What’s ______ most useful invention in the 20th century? —______ computer, I think.

Have you found the information about famous people you can use for the report?Not yet. I’ll search some on the internet.

Do you know that special remedy ____ a cold?

My bedroom is about __________ of the size of yours.

Don’t you think learning English wastes much time?— ____. You haven’t got a proper method, I suppose.