为保障人身安全将电气设备正常情况下不带电的金属部分接叫（）。A、保护接地 B、工作接地

阅读理解。

     Money off your rented textbooks from TextbookRental.ca

     Offer details

     Pay online

     Limit 1 voucher(代金券) per person, may buy 5 more for others

     Shipping is extra (average $6, return shipping included)

     The voucher is valid towards shipping

     Taxes extra

     High spots

     Save up to 75% on every textbook

     Rent books by the semester

     Fast shipping

     Buyback program for your old books

     Make a great gift

     Keeping school expenses low is important. Get a better bargain on academic supplies with today's

WagJag: for $10, receive $25 towards rental textbooks from TextbookRental.ca.

     TextbookRental.ca helps students continue with their study while saving precious money for other

purposes. The site contains books in all academic fields-arts, sciences, business, education and more.

Once you find your desired textbooks, complete the easy checkout process and your course materials

will be shipped to your dorm or home. Discounts on each single book vary but can save you up to 75%.

After the semester finishes, mail back your books (free of marking, stains or other damage), using the

included prepaid return envelope. The site's 15-day return policy lets you send unneeded books back for

a refund.

     Centered in Toronto, TextbookRental.ca has delivery places across the country to make sure

students from Victoria to St. John's get their textbooks in a timely fashion. The site also lets students save

a little money by buying their previously purchased used textbooks.

     If you're not happy with your purchase, let us know why and we'll give you a full refund. Seriously, it's

that simple!

     TextbookRental.ca

     Contact WagJag-WagJag Business Hours are Monday-Friday 9:00 am to 7:00 pm.

     E-mail: info@wagjag.com <mailto:info@wagjag.com>                 Phone: 416-687-5848

     Toll free(免费电话):1-855-492-4524      Fax: 1-866-268-4286

1. The voucher mentioned in the passage _______.  

A. includes shipping fees            

B. will be mailed to buyers

C. can't be used to pay taxes          

D. needs to be cashed at banks

2. What is the main advantage of the service from TextbookRental.ca? 

A. It helps students limit school expenses.

B. It sells new textbooks at a low price.

C. It sends interesting gifts to students.

D. It helps students who are poor at studies.

3. What can be learned about the activity of renting textbooks launched by TextbookRental.ca?

A. It can be enjoyed all over Canada.          

B. It deals with orders 24 hours a day.

C. The books can be returned in any condition.

D. The buyers can keep the books for 15 days.

既能泻下冷积，逐水退肿，又能祛痰利咽治疗喉痹的药物是（）

A.大黄

B.芒硝

C.牛蒡子

D.巴豆

E.芫花

有如下事件过程：　　Private Sub Commaild1_Click( )　　　　Dim i As Integer　　　　For i =1 To 2　　　　　　DC　　　　Next i　　End Sub　　Sub DC( )　　　　Dim x As Integer，m As String　　　　Static y，n　　　　x=x + 1　　　　y=y + 1　　　　m=m&"*"：n=n &"#"　　　　Print x，y，m，n　　End Sub　　程序运行后，输出的结果是()。

A． 1 1 * # 　　 1 1 * #

B． 1 1 * #　　 1 2 * #

C．1 1 * #　　1 1 * ##

D． 1 1 * #　　 1 2 * ##

对“系统”理论的理解，错误的是

A．一个系统是由许多相互关联、相互作用的要素组成的整体
B．闭合系统不具有自我调控能力
C．系统按属性分为自然系统和人造系统
D．系统整体的功能等于各组成部分功能的总和
E．每一个系统都包含上一个系统的次系统

在机加工时，若镗缸时中心定位不准而形成偏心，使气缸的中心线偏移，装配后，将出现（）现象。

A.偏磨

B.正圆柱形磨损

C.上大下小锥形磨损

D.上小下大锥形磨损