二预习词汇和句子 1.all over 3. once a day 3.look after 4.want someone to be healthy 5.bark a lot 6.make too much noise 7. at least 8.three times a week 9.It is a good idea to do sth. 10.It is very important not to do sth. 11.It is necessary to do sth. 12.You do not need to walk them.What should I feed it 13.I’m busy at work all day. 14.She has enough to eat. 二、 课堂合作交流 1.should是建议别人最好做什么事，而must是强调建议别人去做有必要或很重要的事情。
eg when you go out ,you should close the door. As a student, you must finish your homework first. 2.It is necessary to walk them in the park once a day if you want them to be healthy. 句中 It is necessary to do sth,是做某事是有必要的。
eg It is necessary to sleep to health. want someone to be healthy 是想让某人健康。
3.If you have a rabbit ,it is a good idea to clean its hutch every day. 句型it is a good idea to do sth 是做某事是个好主意。
eg It is a good idea to help her with her English . 4.It is very important not to give them too much fool. 句型It is very important not to do sth是不做某事很重要。
eg It is very important not to ride fast on the street . 5.You do not need to walk them.句中need的用法比较多，在句中need用作实意动词，因为它前面有助动词do 所以当need作实意动词时，其后应加动词不定式，need to do sth.此外need 还可作情态动词，其后应加动词原形 need do sth. .否定式 needn’t do sth. 6.She has enough to eat .他有足够的东西吃。句中动词不定式to eat 用来作定语，修饰enough. eg We have enough to drink. I have lots of homework to do every day. 三、课内练习巩固 A翻译短语 1.一天一次 2.想让某人健康 3.制造太多的噪音 4至少 5.做某事是个好主意 6.照看 7.做某事是有必要 8.不做某事很重要 B 翻译下列句子 1.当别人遇到危险时，我们应当帮助他们。
2.你不应该花很多时间看电视。
3.不要浪费时间，你必须睡觉前完成这些题目。
4.小心点，你不应该在马路上骑快车 5.每天陪你的狗玩一会是很有必要的，你应该至少每天陪它走一个小时。
四、课后拓展延伸 1.通过本课学习，同学掌握should与must 的用法 句型It is necessary to do sth. It is a good idea to do sth. It is very important not to do sth. 2.need的用法 五、教学效果验收 1、错题警报 2、错因分析 3、矫正补救 4、教与学反思（教师与学生分别从不同角度）