患者，男性，42岁，神疲易倦、心慌5年余。上小学时曾有游走性关节疼痛病史。查体：心尖

读“等高线地形图”，完成下列问题。（4分）

（1）写出图中字母代表的相应地形部位的名称：A____________，B____________。

（2）若测得A、B两地图上距离约2厘米，两地实际距离是___________千米。

（3）为了加强农田基本建设，实现旱涝保收，村民拟在图示地区建一蓄水量最大的水库，合适的坝址是___________。

书面表达。

     请你阅读你的加拿大网友Tommy的e-mail，根据e-mail的内容，给他写一封回信。

     注意：1. 字数不少于60。

               2. 所给的开头句和结尾不必抄写在答题纸上。

Dear Li Lei,

     I haven't heard from you for a long time. I'm glad to tell you that I'll visit Beijing this summer vacation.

It is said that Beijing is a great city with a long history and more changes have taken place since the 2008

0lympic Games. I would like to know something about Beijing, such as places of interest, the environment,

traffic and people there.

     I'm looking forward to hearing from you soon.

                                                                                                                                      Yours,

                                                                                                                                    Tommy

Dear Tommy,

      I'm glad to know you will come to Beijing. ________________________________________________

_______________________________________________________________________________________

_______________________________________________________________________________________

                                                                                                                                            Yours,

                                                                                                                                             LiLei

临床最常见的慢性头痛是（）

A.丛集性头痛

B.无先兆偏头痛

C.紧张型头痛

D.药物过量使用性头痛

E.有先兆偏头痛

乳牙列建后，如果上下颌第二乳磨牙的远中面，从侧方观察呈上下平齐状态时，将来恒牙列建时会造成（）

A.上下第一恒磨牙易于建立中性关系

B.上下第一恒磨牙易于形成远中关系

C.上下第一恒磨牙易于形成近中关系

D.前牙易形成反

E.前牙易形成超

电动葫芦的限位器是对吊钩上升和下降行程限制的安全装置，因此可以当作行程开关使用。