汽车直线行驶时,由于轮胎的左右轮阻力不同,差速器使两侧驱动轮()。
A、以相同转速旋转B
暂无解析
Itrainedhardyesterday,______preventedmefromgoingtothepark.
Whataretheparagraphqualities?
Newdriversarefarmore________tohaveaccidentsthanexperienceddrivers.
麻疹疫苗初种的年龄是()
Theagriculturalrevolutioninthe19thcenturyinvolvedtwothings:theinventionoflabor-savingmachineryandthedeyelopmentofscientificagriculture.Labor-savingmachinerynaturallyappearedfirstwherelaborwasscarce.“InEurope,”saidThomasJefferson,“theobjectistomakethemostoftheirland,laborbeingabundant:hereitistomakethemostofourlabor,landbeingabundant.”ItwasinAmerica,therefore,thatthegreatadvancesin19thcenturyagriculturalmachineryfirstcame.
Attheopeningofthecentury,withtheexceptionofacrudeplowfarmerscouldhavecarriedpracicallyalloftheexistingagriculturalimplementsontheirbacks;by1860,mostofthemachineryinusetodayhadbeendesignedinanearlyform.Themostimportantoftheearlyinventionswastheironplow.Asearlyas1790CharlesNewboldofNewJerseyhadbeenworkingontheideaofacast-ironplowandspenthisentirefortuneinintrodueinghisinvention.Thefarmers,however,wouldhavenoneofit,claimingthattheironpoisonedthesoilandmadetheweedsgrow.Nevertheless,manypeopledevotedtheirattentiontotheplow,untilin1869JamesOliverofSouthBend,Indiana,turnedoutthefirstchilled-stillplow.?
1.Whatisthemaintopicofthepassage?
a.Theneedforagriculturaladvancestohelpfeedagrowingpopulation.
b.Thedevelopmentofsafermachinesdemandedbythelabormovement.
c.Machinerythatcontributedtotheagriculturalrevolution.
d.NewJerseyasaleaderintheagriculturalrevolution.
2.Theexpression“makethemostof”inLine4isclosestinmeaningtowhichofthefollowing?
a.getthebestyieldfrom
b.raisethepriceof
c.makefulluseof
d.earnalivingon
3.WhichofthefollowingcanbeinferredfromwhatThomasJeffersonsaid?
a.EuropewaschangingmorequicklythanAmerica.
b.EuropehadgreaterneedoffarmmachinerythanAmericadid.
c.Americawasfinallyrnningoutofgoodfarmland.
d.TherewasashortageofworkersonAmericanfarm.
4.Itcanbeinferredthatthewaord“here”inLine4refersto_____.a.Europe
b.America
c.NewJersey
d.Indiana
5.Whatpointistheautormakingbystatingthatfarmerscouldcarrynearlyalltheirtoolsontheirbacks?
a.Farmershadfewtoolsbeforetheagriculturalrevolution
b.Americansweretraditionallyself-reliant.
c.Lifeonthefarmwasextremelydifficult.
d.Newtoolsweredesignedtobeportable.