3. The word "springs" inParagraph 3 means
A a small stream of water flowing naturally from theearth.
B the season of the year，occurring between winter and summer.
C the act or an instance of jumping or leaping.
D a length of metal woundaround，which returns to its original shape after
being pushed.
4. According to Paragraph 4，what does Rome plan to do?
A To make the backpackmore comfortable for the wearer.
B To put the backpack on the market.
C To test the advantage of the backpack.
D To promote the backpack in anewspaper or on television.
5. What is implied in “if you do get oneeventually，just make sure to took both
ways before crossing the street！”?
A You will be too excited to watch the traffic.
B Enjoyingelectronic devices while walking may invite traffic accidents.
C It is notpossible for you to get such a backpack.
D It is wise of you to have such abackpack.
答案与题解：
1.C第一段告诉我们，因为背包可以装许多东西，所以可以将双手解放出来做其他事情：tofree your hands to do other things.
2.A第二段的第一句说，Lawrence C.Rome及其同事们发明的这种背包，当背着背包走路时，会有电能产生；该段最后一句告诉我们，背包的这种性能可减少背包的重量，因为不必携带备用电池。
3.D “springs"在此是弹簧的意思。spring是一个多义词：泉水(A)、春天(B)、弹跳(C)。
4.B 第四段最后一句的意思是：Rome计划将这种背包商业化，即推向市场。A、C、D在文中均未提到。D的意思是为背包做广告。
5.B这个句子的字面意思是：如果你终于得到这样的背包，过马路时一定要两面都看看。也就是说，不要因为同时玩着游戏，听着音乐、看着电视，太专注以致不注意来往车辆了 。