题目

下列对过敏原和抗原比较的叙述中正确的是 A．抗原是大分子或者是具有细胞结构，过敏原也是这样 B．抗原都是大分子，过敏原都是小分子 C．抗原对所有的人都是抗原，过敏原则是对部分人起作用 D．抗原和过敏原的来源是相同的 答案：CWhen I smoked with my family, I would feel so1and good that nothing else in the world seemed so2. I thought that smoking weed (烟草) was okay since many of my family members and people at my school smoked.3ever happened to them.4I started smoking weed a lot more during lunch and after school. I never thought5of it. At that time I just wanted to smoke. Then I began to 6lin school. I would 7classes, come home late and spend all my money. I would spend88 to 18 dollars a day. I never thought9that marijuana (大麻) had a bad effect on those things. Maybe my coming to class high (神智恍惚) was the reason why I was failing or coming home late. As I continued to smoke marijuana, I began to notice that I would always have the strong desire to smoke and that I would get10cigarettes if I smoked those, but I don’t.11I have learned more about marijuana, I have12the amount of marijuana that I use. I don’t want marijuana to be the most important in my life. I’m not smoking every day, and not spending as much money. Since I have13on my habit, I am14more money. I’m ready to go back to school and do good, so that I can make myself15. Everyone is always saying how weed16your mind and how it solves problems. I think it only brings more17. Marijuana is not good for your body or your brain. I’m not trying to tell you not to smoke, I’m just letting you know that marijuana can be18to your health, and19it may cause some long term negative (负面的) effects. Help yourself now, before it is too late. I don’t want to lecture anyone, just20my experience with you. 1.A.worriedB.relaxedC.disappointedD.moved2.A.importantB.commonC.interestingD.funny3.A.somethingB.EverythingC.NothingD.Anything4.A.By the wayB.Now and thenC.In my opinionD.For a time5.A.too muchB.a littleC.too oftenD.any more6.A.get aheadB.fall behindC.come acrossD.make up7.A.giveB.haveC.attendD.cut8.A.at leastB.at mostC.no more thanD.as little as9.A.onceB.twiceC.againD.further10.A.used toB.paid forC.lost inD.ready for11.A.as ifB.Even ifC.Now thatD.As long as12.A.reducedB.increasedC.boughtD.continued13.A.broken downB.cut downC.turned offD.cut off14.A.wastingB.spendingC.makingD.saving15.A.lessB.moreC.betterD.worse16.A.excitesB.fillsC.repairsD.destroys17.A.problemsB.pleasureC.convenienceD.excitements18.A.helpfulB.usefulC.dangerousD.strange19.A.in the beginningB.in the distanceC.in the long runD.in the past20.A.tellB.explainC.regretD.share