1．红水河流域属于           水系。该河段著名的水电站有            电站。

8、    晨昏线的判读

一是根据地球自转方向：顺着方向由夜到昼为晨线，由昼到夜为昏线。

二是根据昼夜半球判断：昼半球西为晨线东为昏线，夜半球西为昏线东为晨线。

7、    确定正午太阳高度

直射点所在纬线正午太阳高度为90度，H=90度-该地地理纬度与太阳直射点纬度差。

6、    确定太阳出没时刻。

纬线与晨线的交点为日出时刻，纬线与昏线交点为日落时刻，同一纬线日出日落时刻相同。

5、    确定昼夜长短

晨昏线将地球上的纬线分为昼弧和夜弧两部分，昼弧和夜弧的长短决定昼长和夜长。弧度15度为1小时。

4、    确定季节

二分日晨昏线过极点，二至日晨昏线与极圈相切

3、某地地方时

赤道与晨线的交点为6时，昏线与赤道的交点为18时，直射点所在的经线为12时，同一经线地方时相同，不同经线东加西减(1度4分钟)

2、确定太阳直射点位置

 在平分昼半球的经线上

1、 确定南北极

(1)、通常上北下南；(2)、自转方向逆时针为北极，顺时针为南极；(3)、经度东经度自西向东逐渐增大。

答案：Ⅰ. 1 ― 5 BDDAA  6 ―10 CABDA  11 ― 15 CCADB  16 ― 20 DBACD  21 ― 25 BDBAC  Ⅱ. 1 ― 5 DBCBA  6 ― 10 CABCA  11 ― 15 CDDAD  16 ― 20 BAAAD   21 ― 25 CBDAB  Ⅲ. 1―5 DACCD  6 ―10 ACDBC 11 ― 15 CFEGD  Ⅳ . 1 . darkness / dark 2 . journey 3 . forced 4 . simple 5 . forehead 6 . wonder 7 . length 8 . satisfied 9 . smelly 10 . zones  Ⅴ . 1 . expected→expecting 2 . 去掉 reached 后面的 to 3 . usually→usual 4. same→the same 5 . 去掉 in 6 . 去掉 for 7 . √  8 . 在 much 前加 how 9 . spend→spending  10 . anyone→everyone

Ⅵ . One possible version:

Dear Mr Zhang ,

We know that this is the last lesson that you will give us . Soon we'll graduate and say good-bye to our school . At this moment , we don't know how to express ourselves . All we can say is "Thanks" .

Three years ago when we came to this school , we knew nothing about English . However , with your unselfish help , we have greatly improved our English in listening , speaking , reading and writing . We owe all this to you , because in the past three years , you have been working hard , trying your best to help us . We will remember all those lively and interesting lessons you've given us , which we will never forget .

Now let us all say again , "Thank you ,  Mr Zhang" .