问题 选择题

若定义在R上的函数f(x)满足:对任意x1,x2∈R有f(x1+x2)=f(x1)+f(x2)+1,则下列说法一定正确的是[ ]

A.f(x)为奇函数

B.f(x)为偶函数

C.f(x)+1为奇函数

D.f(x)+1为偶函数

答案

答案:C

完形填空
As I understand, if scientists produced a human clone, there would be a great risk of it having a disease. Nobody seems to understand the ageing process of a clone. It would be terrible if a baby was the age of its parent at     31   . Its cells would grow old fast and it would die young.    32    until the technique is perfectly safe, it should be     33   .
I'd love to have a clone of     34   . I often wish I had a twin sister, someone who    35   me in everything. So why not a clone? Well, the idea    36   be fun but I'm not sure if it would be     37   . I think we would be playing with fire if we let scientists go ahead with     38   cloning. There are so many     39   
involved that all research in this area should be strictly controlled.
There are so many arguments     40    cloning that it is difficult to get anyone to consider the possible benefits. I am     41    that it is a technique which could be beneficial. The most obvious use would be for childless     42   . They would be able to have babies with their own genetic material. I don't see what's wrong with that.
Imagine a child     43    up knowing that his or her mother is really a sister or a brother. The emotional     44    on the child would be     45   . Or a child who was cloned from a dead brother or sister. What kind of emotional pressure would they feel, knowing they were made as a replacement for another? The whole idea
    46    me!
It's all very good to ban human cloning but scientists should be allowed to   47   
research. If they don't, we may     48    important benefits for our society, such as producing body organs. A clone is an     49    copy of a person with the same gene. Therefore, it is the     50    donor for an organ(器官) transplant.
小题1:
A.home B.lab C.process D.birth
小题2:
A.Besides B.Therefore C.Although D.Unless
小题3:
A.banned B.allowed C.encouraged D.forced
小题4:
A.itself B.herself C.myself D.yourself
小题5:
A.overlookedB.contradicted C.accumulatedD.resembled
小题6:
A.may B.must C.can D.shall
小题7:
A.messy B.safe C.swift D.awkward
小题8:
A.human B.animal C.plant D.pet
小题9:
A.obligationsB.regulations C.formulas D.risks
小题10:
A.against B.with C.for D.amid
小题11:
A.vanished B.convinced C.violated D.teased
小题12:
A.couples B.heroines C.dwarves D.elves
小题13:
A.picking B.looking C.getting D.growing
小题14:
A.pressure B.sample C.privilege D.ambition
小题15:
A.unsinkableB.unimaginable C.unbearable D.unthinkable
小题16:
A.scratchesB.terrifies C.entices D.confronts
小题17:
A.continue B.predict C.tear D.mention
小题18:
A.chase B.contrast C.cure D.miss
小题19:
A.handy B.identical C.contradictory D.transparent
小题20:
A.ideal B.voluntary C.vacant D.inquisitive
单项选择题