请帮我总结一下这几道英语题目的语法点

请帮我总结一下这几道英语题目的语法点
1.People need to use water for bathing and washing clothes.（为什么用bathing,而不用bath)
2.Your clothes will get clean more easily if you wash them under running water.（为什么用easily,而不用easy）
3.People living near the sea can use as much water as they like.（为什么用living,不用live）
4.i begin to learn to raise (as many questions)as i can in maths classes.（为什么是as many questions,而不是questions as many）
5.Every student should (listen to )the rules.Which of the following words is not accepted?（为什么用listen to ,不用obey）
6.Boys and girls!It's time for you to get (cleaned up)（为什么用cleaned up,不用cleaning up)