How it came about that snakes manufactured poison is a mystery. 蛇是怎样产生毒液的，这是一个谜。🎈整句为主系表结构。主从How it came about that snakes manufactured poison是主语， 其中it是形式主语，that主语从句是真正主语。🎈（尤指意料之外的事）发生come about例句How did it come about that he knew where we were?他怎么会知道我们在哪？🎈manufacture v. （身体）产生，制造，分泌(technical) if your body manufactures a particular useful substance, it produces it 例句Diabetics don’t manufacture enough insulin.糖尿病患者无法分泌足量的胰岛素。🎈谁也不知道…是怎样发生的。How it came about that … is a mystery.谁也无法解释… It has never been explained why …例句谁也无法解释玛雅文明为什么会突然从地球上消失。How it came about that Maya civilization vanished from the earth is a mystery. = It has never been explained why Maya civilization vanished from the earth.Over the periods their saliva, a mild, digestive juice like our own, was converted into a poison that defies analysis even today.蛇的唾液本来和我们人的消化液一样柔和，但经过漫长的时间，演变成了今天仍无法分析清楚的毒液。🎈Over the periods是时间状语。a mild, digestive juice like our own是saliva的同位语，其中介词短语like our own作juice的后置定语。定从that defies analysis even today修饰a poison。🎈defy v. 无法…，使…不可能be so difficult as to make (sth.) impossible 无法描述defy description 无法分析defy analysis难以置信defy belief 难以解决defy solution 无法解释defy explanation无法理解defy understanding / comprehension …无法…；不容…be beyond sth.无法修理beyond repair令人无法相信beyond belief无法控制beyond my control不容争辩beyond dispute / controversy无法形容/描述beyond words / description不容指摘beyond reproach / criticism人类无法忍受的beyond human endurance做梦也没想到…（表惊叹）beyond my wildest dreams确定无疑beyond doubt是…所无法/不能…的 be more than … can / could…例句The pain is more than I can bear. 我无法忍受这种疼痛了。It was not forced upon them by the survival competition; they could have caught and lived on prey without using poison, just as the thousands of non-poisonous snakes still do.毒液不是生存竞争强加给它们的，它们也可以不用毒液捕捉动物而生存，就像今天成千上万的无毒蛇那样。🎈把…强加给… force sth. on / upon sb.或impose sth. on / upon sb.把…施加给…exert sth. on / upon sb.🎈they could have caught and lived on prey without using poison相当于they could have caught and lived on prey if they had not used poison，是虚拟语气，表示与过去事实相反。🎈still do中的do指代catch and live on prey without using poison。Poison to a snake is merely a luxury; it enables it to get its food with very little effort, no more effort than one bite.毒液对毒蛇来说只不过是一种奢侈品，它使蛇不用费多大力气就能捕获到食物，轻咬一口即可。🎈with very little effort是方式状语。no more effort than one bite是very little effort的同位语。🎈luxury n.[U]奢侈[C] 奢侈品necessity n.[U]必需 [C]必需品例句Limousines(豪华轿车) and perfumes are luxuries while food, clothing, shelter and transportation are daily necessities.🎈仅仅，只不过no more than …And why only snakes? 为什么只有蛇才有毒液呢？🎈此句相当于And why only snakes （manufacture poison）?Cats, for instance, would be greatly helped; no running fights with large, fierce rats or tussles with grown rabbits—just a bite and no more effort needed.譬如说，如果猫有毒液，那对猫会大有帮助，它就不必再和又大又凶的老鼠边跑边搏斗了，也不必再和大兔子扭斗了，只要咬一口，就不必再费大力气。🎈句中的分号和破折号均起“解释”的作用。for instance是插入语。过去分词needed作effort的后置定语。🎈would be greatly helped是虚拟语气，相当于would be greatly helped if they manufactured poison，结合上下文理解。🎈running adj. 持久的，长时间的lasting a long time; continuous 例句For years he had fought a running battle with the authorities over the land.🎈tussle n. 扭打，搏斗a fight using a lot of energy, in which two people get hold of each other and struggle 与…扭打/搏斗tussle with …和良心作斗争have a tussle with one’s conscienceIn fact, it would be an assistance to all carnivores though it would be a two-edged weapon when they fought each other.因此，任何食肉动物有了毒液，都能从中获益。不过，当它们相互撕打时，毒液就成了利弊参半的武器，可以杀死对方，也可以被对方的毒液杀死。🎈though it would be a two-edged weapon when they fought each other是让步状从，when they fought each other功能相当于if从句（if they manufactured poison）。例句How can I explain it to you when you won’t listen? 如果你不听，我怎么和你解释？🎈it would be an assistance相当于it would be a help，属于表达替换。🎈双刃剑two-edged weapon / sworddouble-edged weapon / swordBut, of the vertebrates unpredictable Nature selected only snakes （and one lizard）.然而，在脊椎动物中，大自然神秘模测地只选择了蛇（还有一种蜥蜴）。🎈of prep. （用于比较时）在……中used when comparing related things 。类似于among，限定一个范围。例句He’s the best looking of the three brothers.他是三兄弟中最俊的一个。One wonders also why Nature, with some snakes concocted poison of such extreme potency.人们弄不清楚大自然为什么在某些蛇的身上调制出如此高效的毒液来。🎈why Nature, with some snakes concocted poison of such extreme potency是宾从，其中with some snakes 是插入语，with表示“对…而言”。🎈concoct v. 调制to produce sth. unusual by mixing things in a new way, esp. a drink or meal 🎈potency n. 效力the strength of sth., esp. a drug, on your mind or body 例句Improper storage may decrease the potency of the drug.存放不当会降低药效。In the conversion of saliva into poison, one might suppose that a fixed process took place. 人们可能认为，唾液转变成毒液，其中有固定的程序。🎈In the conversion of saliva into poison是时间状语。🎈在…的过程中/期间in sth. / doing sth.例句In seeking independence, they do not sacrifice their human dignity.为了/以感谢…in return / reward for …或in appreciation of …[表示一种目的或行为]对（某人的功劳或成就）表示认可in recognition of …为了纪念某人；向某人表示敬意in honor of …[可为生者或逝者]追思/悼念某人in memory of …🎈（计划之中的事情）发生take place （尤指意料之外的事）发生come aboutIt did not; some snakes manufactured a poison different in every respect from that of others, as different as arsenic is from strychnine, and having different effects.其实没有。有些蛇产生的毒液也在各方面与另外一些毒蛇产生的毒液不同，就像砒霜不同于马钱子碱一样。会产生不同的效果。🎈and having different effects和different in every respect from that of others是并列结构，都做a poison的后置定语。that of others中的that指poison，要保证逻辑正确，不能说“毒液和蛇不同”。🎈与…不同be different from …🎈每一方面in every respect / aspect / way🎈就像…与…不同一样 as different as … is from …例句中国文化在各个方面都与美国文化不同，就像大熊猫与白头鹰不同一样。Chinese culture is different in every respect from that of America, as different as the giant panda is from the bald eagle.One poison acts on the nerves, the other on the blood. 一种毒液作用于神经，另一种毒液作用于血液。🎈the other (acting) on the blood是独立主格结构。🎈act v. 有某种效果或作用to have an effect or use 对…产生作用act on …例句Alcohol acts on the brain.作为…（使用）act as …例句Later it was found that there was a type of mosquito which acted as the carrier of this disease and passed it on to the rabbits.The makers of the nerve poison include the mambas and the cobras and their venom is called neurotoxic. Vipers (adders) and rattlesnakes manufacture the blood poison, which is known as haemolytic.产生神经毒液的蛇有一种非洲树眼镜蛇和眼镜蛇，它们的毒液称为神经毒素。蝰蛇（蝮蛇）和响尾蛇产生血液毒素，称为溶血性毒液。🎈(adders)是插入语。🎈被称为… be called …be known as …be referred to as …be addressed as …Both poisons are unpleasant, but by far the more unpleasant is the blood poison.这两种毒液都很可怕，但溶血性毒液尤其厉害。🎈by far …得多(used with comparative or superlative adjectives or adverbs常与最高级或比较级连用) by a great amount 例句The last of these reasons is by far the most important.最后一个原因重要得多。…和…都…，但…多/更…的是… Both … are …, but by far the more … is …例句Both books are interesting, but by far the more interesting is ‘Harry Potter’.It is said that the nerve poison is the more primitive of the two, that the blood poison is, so to speak, a newer product from an improved formula. 据说，神经毒液在两种毒液中是较为原始的一种，而溶血性毒液，打个比方说，是根据改良配方生产的一种较新的产品。🎈好像，仿佛，可谓是，可以说是so to speak =as it were例句He is, so to speak, a walking dictionary.他可谓是一本活字典。🎈formula n. 配方，处方a list of the substances used to make a medicine, fuel, drink etc, showing the amounts of each substance that should be used 例句Our products are handmade from traditional formulas.Be that as it may, the nerve poison does its business with man far more quickly than the blood poison.不过，神经毒辣液比溶血性毒液在人身上起作用快得多。🎈Be that as it may是让步状从。far more quickly than the blood poison作状语修饰does its business，其中than the blood poison是比较状语。🎈尽管是这样Be that as it may = However that may be = Despite that无论发生什么Come what may = Whatever may happen无论刮风还是下雨Come wind or rain = whether wind or rain comes🎈和…做生意；在…上发挥作用do business with …This, however, means nothing.但是，这没有什么关系。🎈不重要，无所谓mean nothing=be not important Snakes did not acquire their poison for use against man but for use against prey such as rats and mice, and the effects on these of viperine poison is almost immediate.因为蛇有毒液不是用来对付人的，而是对付它的猎物，诸如鼠类，毒液对这些猎物会立刻起作用。🎈介词短语for use against man作poison的后置定语。such as rats and mice是prey的后置定语。🎈…对…的效用/影响the effect / influence / impact of … on / upon …🔥必背词汇digestive adj. 消化的，助消化的消化系统/消化器官/消化液digestive system / organs / juices digest v. 1. 消化2.理解，领会1 I find that I don’t digest meat easily.2 He paused, waiting for her to digest the information.digest n. 文摘例句《读者文摘》Reader’s Digestdigestion n. 消化，消化能力；理解，领悟indigestion n. 消化不良；不能理解，不懂carnivore n. 食肉动物herbivore n.食草动物omnivore n.杂食动物vegetarian n.素食主义者【词根】“carn” = flesh肉体carnal a.肉体的，性欲的 E.g.性欲carnal desire carnation n.康乃馨carnival n.狂欢节，嘉年华incarnate v.使具体化 a.人形的incarnation n.（…）的化身reincarnation n.转世，轮回“vor” / “vour” = to eat吃carnivore n. 食肉动物→carnivorous a.肉食性的herbivore n.食草动物→herbivorous a.草食性的omnivore n.杂食动物→omnivorous a.杂食性的voracious a.贪吃的，贪婪的，渴求的voracity n.贪婪devour v.大口吃vertebrate n. 脊椎动物invertebrate n. 无脊椎动物mammal n. 哺乳动物primate n. 灵长类动物rodent n. 啮齿类动物scavenger n. 食腐动物marsupial n. 有袋类动物crustacean n. 甲壳类动物biped n. 两足动物quadruped n. 四足动物prey n. 被捕食者，猎物predator n. 捕食者conversion n. 改变，转变；改变信仰，皈依把…转变成… the conversion of … into …把谷仓变成房子the conversion of a barn into a house把英镑兑换成美元the conversion of pounds into dollars某人信仰从…改为… one’s conversion from … to …他由基督教改信佛教his conversion from Christianity to Buddhismconvert v. 1. 改变（形式或用途）2. 改变信仰把…变成… convert (sth.) to / into sth.让某人（改变信仰）信奉… convert (sb.) to sth.convertible adj. 可改变的convertible n. 1. 可兑换证券2. 敞篷汽车venom n. 毒液n. → adj.有毒的venom → venomous toxin（毒素） → toxicpoison → poisonousnoxious/ hazardous adj.有毒的lethal/ deadly adj.致命的neurotoxic adj. 毒害神经的【词根】“neur(o)” = “nerv” = nerve 神经neural a.神经（系统/中枢）的 neurosis n.神经病neurotic a.患神经病的 n.神经病患者neurology n.神经病学neurological a. 神经病学的neurologist n.神经病学家nerve n.勇气，神经nervous a.紧张的enervate v.使衰弱，使萎靡不振🔥重点表达消化系统/消化器官/消化液digestive system / organs / juices 《读者文摘》Reader’s Digest把…转变成… the conversion of … into …某人信仰从…改为… one’s conversion from … to …把…变成… convert (sth.) to / into sth.让某人（改变信仰）信奉… convert (sb.) to sth.谁也不知道…是怎样发生的。How it came about that … is a mystery.谁也无法解释… It has never been explained why …无法描述defy description 是…所无法/不能…的 be more than … can / could…把…强加给… force sth. on / upon sb.或impose sth. on / upon sb.把…施加给…exert sth. on / upon sb.仅仅，只不过no more than …与…扭打/搏斗tussle with …和良心作斗争have a tussle with one’s conscience双刃剑two-edged weapon / sword或double-edged weapon / sword（计划之中的事情）发生take place （尤指意料之外的事）发生come about…不同be different from …每一方面in every respect / aspect / way就像…与…不同一样 as different as … is from …对…产生作用act on …作为…（使用）act as …被称为… be called …得多by far ……和…都…，但…多/更…的是… Both … are …, but by far the more … is …好像，仿佛，可谓是，可以说是so to speak =as it were尽管是这样Be that as it may = However that may be = Despite that无论发生什么Come what may = Whatever may happen无论刮风还是下雨Come wind or rain = whether wind or rain comes和…做生意；在…上发挥作用do business with …不重要，无所谓mean nothing=be not important …对…的效用/影响the effect / influence / impact of … on / upon …🔥复盘测试消化系统/消化器官/消化液 《读者文摘》把…转变成…某人信仰从…改为… 把…变成…让某人（改变信仰）信奉…谁也不知道…是怎样发生的。谁也无法解释…无法描述是…所无法/不能…的 把…强加给… 把…施加给…仅仅，只不过与…扭打/搏斗和良心作斗争双刃剑（计划之中的事情）发生（尤指意料之外的事）发生…不同每一方面就像…与…不同一样 对…产生作用作为…（使用）被称为……得多…和…都…，但…多/更…的是… 好像，仿佛，可谓是，可以说是尽管是这样无论发生什么无论刮风还是下雨和…做生意；在…上发挥作用不重要，无所谓…对…的效用/影响
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