The man called his professor for help because he couldn’t solve the problem by _________.

Sandy, _______ apple on the table is for you. Remember to eat it.—Thanks, I will. _____ apple a day keeps the doctor away.

In Africa , the weather there is often_______

Is that Mr. Wang speaking?—Sorry. He isn’t at home. He ________ abroad for a trip.

You can improve your English ______ reading more. [ ]