为了除去NaCl溶液中少量的MgCl2、Na2SO4，从稀盐酸，Na2CO3，K

病历摘要：患者，女性，妊娠38周，发现肛周赘生物2天，稍有痒感。自诉2个月前曾有外阴溃疡史，无痛，无痒，未诊治，自愈。配偶有婚外性生活史。查体：肛周可见数个暗红色、直径1～3cm的扁平疣状损害，基地宽，无蒂，表面少量渗液。

该患者非梅毒螺旋体抗原血清试验及梅毒螺旋体抗原血清试验皆为阳性，组织液暗视野检查找到螺旋体，则该患者的正确诊断是（）

A.一期梅毒

B.二期梅毒

C.三期梅毒

D.隐性梅毒

E.胎传梅毒

F.神经梅毒

下列选项中对美国政体理解正确的是                                                              （   ）

A．政府对国会负责

B．总统可以兼任议会议员

C．行 * * 属于国会

D．国会是立法机关

What is eBay? The simple answer is that it is a global trading platform where nearly anyone can trade practically anything. People can sell and buy all kinds of products and goods, including cars, movies and DVDs, sporting goods, travel tickets, musical instruments, clothes and shoes — the list goes on and on 

The idea came from Peter Omidyar, who was born in Paris and moved to Washington when he was still a child. At high school, he became very interested in computer programming and after graduating from Tuft University in 1988, he worked for the next few years as a computer engineer. In his free time he started Bay as a kind of hobby, at first offering the service free by word of mouth. By 1996 there was so much traffic on the website that he had to upgrade (升级) and he began charging a fee to members. Joined by a friend, Peter Skill, and in 1998 by his capable CEO, Meg Whitman, he has never looked back. Even in the great crashes of the late 1990s, ebay has gone from strength to strength. It is now one of the ten most visited online shopping websites on the Internet 

Ebay sells connections, not goods, putting buyer and seller into contact with each other. All you have to do is lake an e-photo, write a description, fill out a sales form and you are in business.  The world is your market place. Of course for each item, eBay gets a percentage and that is a great deal of money. Every day there are more than sixteen million items listed on eBay and eighty percent of the items are sold.

42. We learn from the text that eBay provides people with _________.

A. a way of buying and selling goods 

B. a place to show their own photos

C. a website for them to upgrade

D. a chance to buy things at low prices 

43. Why did Peter create eBay after graduating from university? 

A. For fun                                     B. To make money 

C. For gathering the engineers                            D. To fulfill a task of his company 

44. From “he has never looked back” in Paragraph 2 we learn that Peter _________.

A. did not feel lonely                             B. was always hopeful 

C. did not think about the past                             D. became more and more successful 

45. How does eBay make money from its website? 

A. By bringing sellers together.                             B. By charging for each sale 

C. By listing items online                             D. By making e-photos.  

伏地后扫的易犯错误有哪些？如何纠正？怎样教好？

交易系统登录密码设置有哪些要求？（）

A、只能是数字

B、必须是数字和字母

C、只能是字母

D、密码长度6－10位