根据句意用所给词的适当形式填空 1. Chinese people like using_____(wood)chopsticks. 2. We should take the bus or subway instead of _________(drive). 3.The mobile phone ________ (花费)me 2000 yuan 4. Don't _________ (扔垃圾)everywhere. 5.Taking some_______(act) to protect our envrionment is necessary. 6The river has _________ (pollute) badly.