用所给词的适当形式填空。(5分)
Tea plants are       (grow) on the sides of mountains.
—Do you know Liu Shenglan?
—Yes, I do. He is very kind and     (help).
Don’t shout at your mother. Your parents should be spoken____(polite).
Although the man was a     (strange), I tried my best to help him.
—You used to       (are) short, didn’t you?  —No, I didn’t.