—Are these books ________? —No, they are not mine. They belong to ________.
—The spacecraft has never been to the moon, ________ ?—Certainly.
—Miss Li has taught ____ English for about 3years.—You are lucky. ____ is a very good teacher.
—How long has John been here? — Two years, _______ he still has no friends.
—Excuse me. Could you tell me ________? — Sorry, I am new here.
— ______ the earthquake in Yushu is! — Yes, we should try our best to help them.