She can’t ride a bike. She ______ school on foot.A. must get to B. has to get to C. has to go to
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?