There is a ______ of furniture in the market, which can satisfy all the customers’ demand.

The girl has a great interest in sport and ____ badminton classes twice a week over the last three years.

It’s hard to say what kind of person he is. Sometimes he is very nice; at other times he _______ be very cold.

What is month of a year—It’s December.

They soon ______ doing the same thing day after day, and finally gave up.