1.5，　 -2，　 2，　 -2.5，　 　，　 0.

2、利用上面的数轴表示下列有理数

1、请画好一条数轴　

2、自己动手操作，看看可以表示有理数的直线必须满足什么条件？

引导归纳：

1)、画数轴需要三个条件，即　　　 、　　　　 方向和　　　　　　 长度.

2)数轴

1、由上面的两个问题，你受到了什么启发？能用直线上的点来表示有理数吗？

2、在一条东西向的马路上,有一个汽车站,汽车站东3m和7.5m处分别有一棵柳树

和一棵杨树,汽车站西3m和4.8m处分别有一棵槐树和一根电线杆,试画图表示这一

　 情境?

东

　　　　　　　　　　　　　 汽车站

请同学们分小组讨论，交流合作，动手操作

1、观察下面的温度计,读出温度.分别是　　　 °C、　　　 °C、　　　　 　°C.

49. right　 　　　　　 50. offers　 　　　　 51. ourselves　 　　　 52. Actually　 　　 53. basis

[书面表达]

I’m writing to tell about the discussion we’ve had in the recent class meeting about whether Senior 3 students should take a lot of tonics to keep fit.

Opinions are divided on the topic. Sixty percent of the students think it unnecessary to take any tonics. They hold the opinion that taking tonics will cause them to put on weight, which is bad for their health. What’s more, the price of tonics is rather high.

However, forty percent of the students point out that Senior 3 students have a lot more homework to do every day. So many students get tired and tonics can help to refresh themselves. In addition, they can’t afford time to have sports.

Personally, having right food is more important. The best way to stay healthy is to take exercise regularly.

44. behave　 　　　　 45. that　　 　　　　　 46. both　　 　　　　 47. way　　 　　　　　 48. try

43. A。综合全文可知。

[对话填空]