分类：教育/科学-学习帮助
问题：一道选择题Youhaveto______yourvoice___ 
You have to______ your voice ______ if you don't li to be criticizedA.turn down    B.turn on    C.keep  down   D.put down
回答：C
turn down 转下来
turn on 打开
keep down 控制
put down 放下