These apples look very beautiful.- They ________. See the price $ 3.99 a pound. Very expensive, aren’t they?

Rick has learned a lot about Chinese culture he came to China.

How long has this shop _____—For about three weeks.

Linda, I called you this morning, but nobody answered the phone.—I’m sorry. I ________ football with my friends then.

It is well known that knowledge is________treasure house，but practice is________key to it.