用所给单词的适当形式填空

【1】Do you know how______（drive）a car?

【2】We Chinese are used to______（eat） with chopsticks．

【3】The question is really difficult for us ______（understand）．

【4】We should ______（plant）more trees to make our city beautiful．

【5】I have a friend who ______ （play）the piano well．