2021军队职称英语考试理工类完形填空讲义（3）

Cell Phone Lets Your Secret Out
Your cell phone holds secrets about you.Besides the names and 1 that you've programmed into it，traces of your DNA2 linger on the device，according to a new study.
DNA is genetic material that 2 in every cell.Like your fingerprint，your DNA is unique to you 3 you have an identical twin.Scientists today routinely analyze DNA in blood，saliva，or hair left 4 at the scene of a crime.The results often help detectives identify 5 and their victims.Your cell phone can reveal more about you 6 you might think.
Meghan J.McFadden，a scientist at McMaster University1 in Hamilton，Ontario，heard about a crime in which the suspect bled onto a cell phone and later dropped the 7 This made her wonder whether traces of DNA lingered on cell phones——even when no blood was involved 8 she and colleague Margaret Wallace of the City University of New York analyzed the flip-open phones3 of 10 volunteers.They used swabs to collect 9 traces of the users from two parts of the phone：the outside，where the user holds it，and the 10，which is placed at the user's ear.
The scientists scrubbed the phones using a solution made mostly 11 alcohol.The aim of washing was to remove all detectable traces of DNA.The owners got their phones 12 for another week.Then the researchers collected the phones and repeated the swabbing of each phone once more.
The scientists discovered DNA that 13 to the phone's speaker on each of the phones.Better samples were collected from the outside of each phone，but those swabs also picked up DNA that belonged to other people who had apparently also handled the phone.14，DNA showed up even in swabs that were taken immediately after the phones were scrubbed.That suggests that washing won't remove all traces of evidence from a criminal's device.So cell phones can now be added to the 15 of clues that can clinch a crime-scene investigation.
词汇：
linger v.逗留
flip-open phone翻盖手机
genetic adj.遗传的
swab n.药签
saliva n.涎，唾液
scrub v.用力擦洗；擦净
bleed v.流血
clinch v.确定，决定
注释：
1.McMaster University：麦克马斯特大学，位于加拿大安大略省汉密尔顿市，成立于1887年。
2.DNA：脱氧核糖核酸。系deoxyribonucleic acid的缩写。
3.flip—open phones：翻盖手机。又可作flip phones.
练习：
1.A numbers B music C secrets D films
2.A appeals B appoint C appears D applies
3.A because B unless C although D still
4.A about B in C for D behind
5.A criminals B people C men D policemen
6.A when B until C before D than
7.A device B paper C file D document
8.A However B So C But D Nevertheless
9.A invisible B non-existent C visible D apparent
10.A card B keys C screen D speaker
11.A of B up C on D into
12.A upon B back C without D with
13.A was given B belonged C was owned D became
14.A Generally B Surprisingly C Disappointedly D Shortly
15.A explanation B discovery C book D list
答案与解析：
1.A人们通常在手机中储存人名和他们的电话号码。所以A是最佳选择。虽然手机中也能储存音乐和秘密信息，相比之下，不如A合理。至于储存电影片子，就有点离谱了。
2.C这个句子的意思是：DNA是一种存在于每一细胞中的基因物质。根据这一理解，选项A、B、D均不能选作答案。
3.B上文的意思是：如同指纹，你的DNA是独一无二的。因此，此处必须选择unless，其他选择均不符合句义，也违背了我们对DNA的基本常识。
4.D leave behind是固定搭配，意即：留下。此处leave使用的是过去分词形式。
5.A根据上下文的理解，研究结果是用来帮助侦探识别罪犯和受害人的，B、C、D都不能表达这一层意思。
6.D句子中的more提供了选择的线索，more…than的搭配最能完成该句的意思。
7.A定冠词the说明该选项所指内容在前面已经提到，即cell phone.除了device，其他选项均不能指代cell phone.
8.B四个选项中只有B是正确选择。s0连接了其前后两个句子，使其形成因果关系：她思考微量DNA是否会停留在手机上，所以，她与同事们一起对10名志愿者的翻盖手机进行了分析研究。A、C、D表示的都是转折的意义关系。
9.A句子当中的paces指的是DNA traces（微量DNA），而DNA paces是肉眼看不到的，所以选择invisible.
10.D研究者从手机的两部分收集手机微量DNA：一是手机外壳，二是喇叭。贴在耳朵上的不可能是card、screen和keys.
11.A be made of是固定搭配，意即：由…制成。a solution made mostly of alcohol：一种主要由酒精制成的溶液。
12.B根据上下文的理解，应该选择back：手机拥有者拿回了手机，再使用一个星期。
13.B该句要表达的意思应该是：科学家在每一个手机上发现了属于手机拥有者的DNA.belong t0是固定搭配，意思是：属于。A不符合句义，c和D不符合语法。
14.B最后一段的第一和第二句告诉我们手机经过清洗后仍然有微量DNA出现。所以这里要用surprisingly这个副词，表示令人惊讶。
15.D根据上下文的理解，应该选择D，其它三个选项与句子的意思不符。