— _________ do you have an Art Festival in your school?   — Once a year.

.Do you know ______ to deal with the problem? Could you tell me?

 -------The box is ____ heavy for me to carry. Can you help me? ------- Certainly.

--- ____homework is required for a middle school student every day ?          ---About two hours .                                            

Thanks to the Internet , the world seems to become           .