Unit 13 We’re trying to save the earth.. 知识点 1 Unit 13 We’re try ing to sav e the earth. Section A 1. 区分voice,sound 和 noise (1)voice 一般指人的声音，如说话，唱歌，但有时也可指鸟叫的声音。The girl has a beautiful voice. (2)sound 指人能听见的任何声音。Sound travels more slowly than light. (3)noise 常指不悦耳、不和谐的嘈杂声。The noise wakes me up. The boy didn’t sleep well last night because of the_____from the factory. A.voice B.noise C.music D.song 2. (1)more 是 many和much 的比较级,既可修饰可数名词复数,也可修饰不可数名词,意为“更多的” more students 更多的学生 more food 更多的食物 (2)less 是 little 的比较级,修饰不可数名词,意为“更少的” less polution 较少的污染 (3)fewer 是 few 的比较级,修饰可数名词复数,意为“更少的” fewer students 较少的学生 (1)If there were more trees on the earth,there would be l pollution. (2)All of us want to do more work with time and workers. A;fewer;less B;less;fewer C;more;much D.less;more 3. (1)used to do sth.表示过去习惯性的动作或经常性的状态. He used to smoke,didn’t he? (2)be used to doing sth 表示“习惯于做某事” My parents are used to getting up early. (3)be used to do sth=be used for doing sth 是被动结构，表示“被用来做某事” The knives are used to cut things.=The knives are used for cutting things. (1)She used to with her parents, but now she is used to___with her classmates at school. A. live; living B.live; live C.living; living D.living; live (2)Keys______ used for ______ the doors. A. is, opening B. is, opened C. are, opening D. are opened Unit 13 We’re trying to save the earth.. 知识点 2 4. 辨析：be able to 和can (1)be able to 可用于各种时态,表示经过努力而获得的能力. (2)只有现在式(can)和过去式(could).表示自身已具有的能力或有能力做某事. (1)He could play the guitar when he was five years...
