1.Ifyou_________(go)tothelecturelastSaturday,you__________(benefit)alotfromit. 2.IfI___________(run)outofink,Iwouldhavefinishedwritingthepaper. 3.________forthetimelyinvestmentfromthegeneralpublic,ourcompanywouldnotbesothrivingasitis. A.HaditnotbeenB.WereitnotC.BeitnotD.Shoulditnotbe 4.___________methemoneyformytuitionthen,Iwouldbeworkingonthefarmnow. A.Shouldn’tmyunclelendB.Hadmyunclenotlent C.WouldmyunclelendD.Ifmyunclenotlent 5._________thefog,weshouldhavereachedourdestination. A.BecauseofB.InspiteofC.IncaseofD.Butfor 6.Itisimportantthatthecommittee________(inform)abouttheprojectatonce. 7.Thecommitteemembersproposethattheplan___________postponedforafewdays. A.tobeB.beC.beingD.been 8.Iwishourteacher________(go)togiveanothertest.Ihaven’tgotpreparedyet. 9.Ifonlythecommittee_______(approve)theregulationsandputthemintoeffectassoonaspossible. 10.It’shightimeyou__________(start,work) 11.Frankly,I’dratheryou_________(not,do)anythingaboutitforthetimebeing(当前). 12.Iwouldhavecalledyouifl__________(know)yourtelephonenumber. 13.Theteacherinsistedthatwe______(finish)ourhomeworkbefore9o’clock. 14.________(arrive)beforewedepartthedayaftertomorrow,weshouldhaveawonderdinnerparty. 15.Idon’tthinkitadvisablethatTom__________(assign)tothejobsincehehasnoexperience. 16.Heisapoorlylearntman.Butheactsasthoughhe___________. A.isB.wereC.shouldbeD.seemslike 17.Doctorssuggestedthattextbooksandnotebooks__________(print)onyellowpaper,whichwouldbebetterforeyes. 18.Iinsistthatadoctor__________(send)forimmediately. 19.Itisnecessarythataperson____________exerciseseverydayifhewishestobehealthy.A.doesB.didC.doD.takes 20.Iwasverybusythatday.OtherwiseI_________(take)partinthediscussion. 21.Ifmylawyer________(be)herelastSaturday,he______(prevent)mefromgoing. 22.Ishouldverymuchliketogototheparty,butI_________________(not,invite). 23.IfI________(be)you,I’djointhearmy. 24.Ifyouhadwantedtobuyarecord,what__________(buy)? 25.___________(leave)today,hewouldgettherebyFriday. 26.Jimwouldratherwe_________(not,leave)now,butwemustgotowork. 27._________Tom_________(look)atthepricelist,he’dhaveknownwhattoexpect. 28.Mysuggestionisthattheexperiment___________(do)inanotherway. 29.LookattheterriblesituationIamin!IfonlyI____________(follow)youradvice. 30.Itishightimethatsuchapractice__________(put)anendto. 31.___________(come)tomorrow,hewouldbeabletoseetheopeningceremony. 32.IfI___________(have)moretime,Iwouldhavegonewithhim. 33.Theideaisthatthenation__________(send)anunmannedspacecrafttoexploretheplanetfirst. 34.Itisnecessarythatyou__________(be)thereinperson. 35.Werequiredthatthemachineparts____________(make)ofiron. 36.Themanagementurgedthatthecostofproduction__________(reduce). 37.Thebusinessisrisky.But__________wewouldberich. A.shouldwesucceedB.weshouldsucceed C.mightwesucceedD.wouldwesucceed 38.IfI_________(live)inthetwentyfifthcentury,I____________（spend）myvacationinaverydifferentway. 39.Itisrequiredthatthemachine________(oil)asfrequentlyasnecessary. 40.HisEnglishteacherrecommendsthathe_________(begin)aregulardegreeprogram.

比较C≡C, C=C, C─C, C=C─C=C的键长次序为: C=C─C=C>C─C> C≡C >C=C|C=C─C=C>C─C>C=C>C≡C|C≡C>C=C>C─C>C=C─C=C|C─C>C=C>C=C─C=C>C≡C|C─C>C=C─C=C>C=C>C≡C

下列哪种主链骨架原子排列最能代表两个肽键?() A: Cα—N—Cα—C—Cα—N—Cα—C B: Cα—N—C—C—N—Cα C: C—N—Cα—Cα—C—N D: Cα—C—N—Cα—C—N E: Cα—Cα—C—N—Cα—Cα—C

比较C≡C(Ⅰ),C=C(Ⅱ),C─C(Ⅲ),C=C─C=C(Ⅳ)的键长次序为( )。 A: Ⅰ＞Ⅱ＞Ⅲ＞Ⅳ B: Ⅲ＞Ⅱ＞Ⅳ＞Ⅰ C: Ⅲ＞Ⅳ＞Ⅱ＞Ⅰ D: Ⅳ＞Ⅲ＞Ⅱ＞Ⅰ

不稳定的一类化合物是: C≡C|C－C|C＝C|C＝C－C＝C|C＝C＝C

NaNH4HPO4水溶液的质子条件式为 A: c(H+)+c(H2PO4-)+2 c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) B: c(H+)+c(H2PO4-)+ c(H3PO4)=c(OH-)+c(NH3) +c(PO43-) C: c(H+)+c(NH3)+ c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-) D: c(H+)+c(NH3)+ 2c(H3PO4)=c(OH-)+c(PO43-) +c(H2PO4-)

比较C≡C(I)，C=C(II)，C─C(III)，C=C─C=C(IV)的键长次序为：

在同一种固体介质中，纵波、横波、表面波三者之间的声速关系为（） A: C﹤C﹤C B: C﹤C﹤C C: C﹤C﹤C D: C﹤C﹤C

scanf(“%c%c%c“, &a,&b,&c)与scanf(“%c %c %c“ ,&a,&b,&c)的输入（ ）。

能产生共轭效应的是 A: C=C=C B: C=C C: C≡C D: C=C-C=C E: C-C