of the height of the depth wheel or where a depth wheelis not fitted, by a setting on the hydraulic depth control.When the depth is set, the beam should be set horizontalby adjusting the top link and the plough level by adjusting the lifting rod.Width of furrow may in some cases be altered by chang-ing the position of the disc in relation to the beam towhich it is attached@. This can envolve,in effect, slightrotation of the disc so that the angle of the disc to theline of pull is greater or less. Whilst this will alter the fur-row width it will also make the plough moredifficult topull and cause the furrow to be thrown farther sideways,if the angle is made greater. Alteration of the vertical an.gle of the disc will affect penetration by the disc. The morevertical the disc,the greater will be the penetration.The rear wheel of a disc plough is spring loaded tomaintain a pressure causing it to cut into the soil and itis also set to run at an angle to counteract the considera-ble side thrust set upon the plough when the furrows aremoving over the discs. On some ploughs there may be ver-tical and lateral adjustment on this wheel to correct anytendency of the plough to swing at the rear.Words and Expressionstotally['toutali]ad.完全climate["klaimit]n.气候unsuitable[An'sju:tabi]a不适宜reclamation[rekla'meifan]n.开的，不合适的莞，垦殖conventional[kon'venJonl]a.传统root[ru:t]n.根的；通用的tropical['tropikal]a.热带的temperate['temporit]a.（气候）温bake[beik]v.烤，烘和的likely["laikli]a.（似有)可能的moist[moist]a.湿润的~.o.do能.的8
wheelfavour["feiva]n.好意，欢心bite[bait]vt.咬住，抓住be in~受欢迎satisfactorily [rsaetisifektarili]ntrol.invert[in'vait】yt.翻转，翻过来令人满意的ontalconcave[kon'keiv]a.回的adjustment[o'dsastmont]n,调Ajust-~disc凹面圈盘调节similar【'simila]a.同样的，类似的link[link]拉杆be~to类似于....top上拉杆nang-byanymeans无论如何；总而言之right-hand["raithaend]a.右手的ntodentical[ai'dentikol]a.同一的，右边的完全一样的slightrod[rod] n.杆function[fankfen]n.功用，作用lifting~提升杆therotate[rou'teit]vi.转动，旋转alterationLoilto'reifan]n.改变fur-so-called['souko:ld]a.所调变更Ittorise[raiz]vi.上升，升高height[hait]n，高，高度concavity[kon'kaeviti]n.凹处[width[wido]n.宽，宽度ways,面relation[ri'leifon]n.关系an-throw[erau](threw,thrown)vt.关于与有关抛，扔moreenvolve(involve)[in'volvl yt.sideways['saidweiz]ad.斜着，从旁含边effect[i'fekt]n.结果，作用dtotidy['taidi]a.整齐的#~实际上aditeven["i:von]a.（表面）平坦的rotation[rau'teifon】n.转动normally['nomoli]ad.正常地pall[pul]n.牵引:拉力dera-weed[wiid]n.杂章lineof~牵引线，拉力线areupto直到..whilst["hwailst](=while)conj.ver-implement['implimont]n.机具，时，而农具farther[fa:o]ad.较远，更远anyutilize[jurtilaiz]yt,利用affect[o'fekt]vt.影响assist[o'sist]vt.辅助，协助maintain[men'tein]yt.支持，保持polydise["polidisk】a.多圆盘的保养～plough多圆盘型，垂直固盘型counteract[kauntoraekt] vi.approximately [o'proksimitli] ad.considerable[kon'sidarob]a.相大约，差不多大(或多)的n.开plain[plein】a.普通的；简单的lateral[letorol】a.侧向的，横向cutaway[katowei】a.峡口的，面tendency["tendansi]n.倾向，趋】的swing[swin]vi.&n.摇摆，摆动effectively[ifektivli]ad.有效地，rear[ria]n.尾部有力地的
Notes except perhaps to carry out reclamation work or to plough landin whichthereis much stoneand treeroot:或许除开垦荒地或翻耕石头、树根较多的耕地之外。不定式tocarryout和toplough作介词except的宾语。② This plough is unlike the mouldboard plough in that it does nothave.这种犁与锦式翠的不同之处在于它没有。其中that为连词（无实际意义），它引导的从句作介词的宾语。? which carries out a similar but not by any meansidentical functiontothemouldboardandshare:圆盘的功用与犁壁、型锌类似，但并不完全相同。which引导的是定语从句，修饰disc;similar和identical共用一个介词短语tothemouldboardandshare作状语。④thediscsrotate...andthenthrown sideways:句中分调短语cuttinginto thesoil 作状语，表示伴随rotate产生的动作，不定式to raise和被动态不定式tobebroken及（tobe)thrown并列，作主语furrowslice的补足语。本句可译为：圈盘旋转切入土填，使所谓的堡片沿圆盘的固面升起、破碎，然后被抛到一侧。?Tidy,even, completely inverted furrows are not normallyproduced,nor aretrash and weeds buried as with a conventional plough.中“not（或neither）.nor”意为“既不.，也不”在以nor开头的分句中主谓语须倒装或部分倒装，本句为部分倒装，只把助动调are放在主语trash和weeds之前；aswith意为“如同..的情况一样”，由于其前有否定词not和nor，故意义相反。全句可译为：（圈盘型）和传统翠不一样，既不能翻耕出整齐、均勾、完全翻转的堡片，也不能复盖住残茬杂草。6Disc ploughs may be trailed or mounted as are the mouldboardploughs.句中as为关系代调，代表主句中的表语trailedormounted，并在从句中作表语，该从句倒装，主语为themouldboardploughs。全句可译为：圆盘翠和锌式型一样，有牵引式和悬挂式两种。?whenworkinginhardconditions相当于whenit（代表implement)isworking in hard conditions③to enableitto becarried byatractor:使它能为拖拉机所带动。该不定式短语做状语，表示结果，修饰lighter，动调enable（意为使...能.）后要求宾语及不定式作宾语补足语，tobecarried为不定式tocarry的被动态。?So that the plough can be made to work satisfactorily in various10
conditions:为了使攀在各种条件下都能面满地进行作业。so that目的状语从句，它被置于主句之前，具有强调意味。10adjustment to the top link and/or the right-hand lifting rod sertoleveltheplough：调节上拉杆和（或）右侧提升杆，即可把型调平。adjuandmentto....意为“对的调节"，and/or富为“和（或）”在此指两者翻耕调节或只调节其一，serve+inf.意为“足以"或者“作用是使”。个词@ the position of the disc in relation to the beam to which it istached:圆盘与固定圆盘的型染之间的相对位置。介词短语 of the dnot和 inrelation to thebeam均作定语，修饰 position。连词ion下完专用ing和ow盘的ed,可中#的放在共不。arded,句nt)不·能tous
3.TOOTHEDHARROWSHarrows are employed for a great variety of purposes,such as the preparation of seed beds, the.covering of seeds,the destruction of weeds and the aeration of pastures. Manytypes and sizes are used for carrying out these widely-dif-fering functions.The most common and simple type is thatwith a zig-zag iron frame and rigid teeth@. The range ofzig-zag tractor harrows may be conveniently specified byreference to the thickness of the teeth, which usuallyranges from about 1/2 in. square to 3/4 in. square.Seeds harrows are light implements with straight, close-ly spaced teeth, not over 1/2 in. thick and about 4 inlong. Owing to the zig-zag construction of the frame theteeth are staggered so that those at the rear do not followin thetracks of the front ones.These implements areemployed for the final touches in the preparation of fineseed-beds and for covering seeds after the drill. Sets ofseeds harrows and slightly heavier light" harrows from 20to 30 ft. wide are available for tractor work, and are easilywithin the capacity of small machines@. When they areused for covering seeds, harrows are frequently hitched di-rectlybehind the drill.The handiest equipment for this purpose, however, is adevice supplied by the drill manufacturer and usually con-sisting of a row of spring coverers which can be adjustedto suit the conditions.12