与别人道别时,我们应该说_________A、Hello! B、See you .
( ) -- Hi, Mike. Can you help me? -- OK. ________.
( )Even the top students in our class can't work out this problem. So it _____ be very difficult.
( )This machine is very easy to use.______ can learn to use it in a very short time.
( ) One of his friends ______ his daughter sometimes.
( )The game is _____ funny that many of them like it.