The foreigners are ______ by the ________ progress that the Chinese have made.

I’m sorry I often feel weak or fall ill at school.—Keep ________ more after-school activities, and you will feel better soon.

What _______ news it is! Nobody _____ it.

They must have gotten to the top of the mountain by now. They_____ before the sun rose.

ike fingerprints, each person’s DNA is ________unlesshe has a twin.