Touch your eyes with your fingers _____________ . A. ten times B. ten time C. for ten times
( )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.
( )Are there _____ trees behind the house?