Sometime is knocking at the door. Who ______ it be? --It ______ be Tom. He is still in the school.
All the clerks went home _________ Mr. Yang,for he had to finish his work.
----Don’t forget to give my best wishes to your uncle.----_________.
----Whose book is this?----It _______ our geography teacher’s. You see, his name is on it.
---- Mom , I was the first to reach the top of the mountain .--- Good job, Jack! I 'm ______ of you.
There is ______ American boy in our class and ______ boy can speak good Chinese .