根据句意用所给词的适当形式填空。(每空一词 4分)
It is ________( use ) to talk to him like that. He won’t listen to you.
Please mix the red ___________(strawberry),green pears, purple grapes and oranges together.
Today it's becoming more and more important for students to learn to teach _______.(they)
The boy is more than 2 meters in ____________(high) and he is good at playing basketball.