1.contradiction n.矛盾(a statement or phrase whose parts contradict each other);反驳(act or an instance of contradicting)

词根记忆：来自contradict(v.反驳；否认)

例:It indicates why a contradiction described in the previous paragraph has been overlooked by historians.

2.contrast n.对比;差别(the difference or degree of difference between things having similar or comparable natures)v.对比;使与对照(to compare or appraise in respect to diferences)

例:In contrast, in the year prior to the tax increase, sales had fallen one percent.

派生词：contrastive(a．对比的)

3.contribute v.贡献(to play a significant part in bringing about an end or result)；投稿(to submit articles to a publication);捐献(to give or supply in common with others)

词根记忆：con(全部)+tribute(给予)--全部给予--捐献

例:Automobiles become less fuel efficient and therefore contribute more to air pollution as they age.

派生词：contribution(n.贡献;捐献;投稿)

同根词：attribute(v.归属；把…归于)

4.contributor n.贡献者，捐助者(one that contributes a sum of money)；投稿者(a writer who submits his articles to a publication)

词根记忆：来自contribute(v.捐献)

例:Sulfur dioxide,a major contributor to acid rain, is an especially serious pollutant because it diminishes the respiratory system's ability to deal with all other pollutants.

派生词：contributory(a．捐献的;贡献的)

同根词：tribute(n．赠品)

5.control v.控制，管理(to rule);n.（实验的）对照，参照物(an individual or group used as a standard of comparison in a control experiment)

词根记忆：control作为“参照物”的意思时是专业术语

例:It served as a controlfor the experiment.

6.controversial a．引起或可能引起争论的(causing controversy)

词根记忆：contro(相反)+vers(转)+ial--反着转--引起争论的

例:The relationship between corpulence and disease remains controversial

派生词：controversially(ad.颇有争议地)

同根词：controvert(v.争论；辩论)

7.controversy n.争论，辩论(dispute)

词根记忆：contro(相反)+vers(转)+y--意见相反一争论，辩论

例:There are some possible approaches to resolving this long-standing controversy.

派生词：controversial(a．争议的，争论的)

8.convection n．对流(the circulatory motion that occurs in a fluid at a nonuniform temperature owing to the variation of its density and the action of gravity)

Theoretically, this convection would carry the continental plates（板块）along as though they were on a conveyor belt. ．

9.convenience n.便利(fitness or suitability for perfoming an action or fulfilling a require-ment)

联想记忆：con（共同）+ven（来）+i+ence--共同行动来维护便民设施一便利

例:People buying pancake syrup at convenience stores,unlike those buying it at supermarkets,generally buy it only a few times.

同根词：convene（v.召集）

10.Conventiona a.医印看守旧的(according w．th a mode of artistic representation that simplifies or provides symbols or substitutes for natur a forms)；传统的(0f traditional design)

词根记忆：来自convention（n.习俗，惯例）

例:Conventional wisdom has it that Iarge deficits in the United States budget Cause interest rates to rise.

派生词：conventionally（ad按照惯例地）

同根词：convene（v.召集）