--- He didn’t go to the concert yesterday, did he?--- _____. He was busy studying for the test all day.
—He got up as early as possible________he could get to school on time.
The________junk food you eat, the________you will be.
— The problem is a bit difficult . — ________ask your teacher for help?
—Did you know that the earth is the home of animals?
—Which country has________population ,China , India or America? — China.