细心整理Structure 句型Lesson 15 in some part of the world people are still____b__ to write A incapable b impotent c enable d unable6 they can preserve their history _____d_ down legendsA by hand b by handing c to hand d in hand7the ____a__ why these legends are useful is that they tell us about migrationsA cause b effect c why d reason8 there weren't ___a___ of then who could write down what they did.A any b none c no one d noLesson 25 it would ____a__ impossible for us to live in this world if insects had no enemies.A make it b stay c be d have it 6 we owe __c____ to the birds and beast who eat insects.A a great deal b a lot of c a great many d much of7 how many spiders are involved _____a_ this work on our behalf?A at b for c in d to 8 there are many different ___a___ spidersA sort of b kind of c type of d kindsLesson 35 earlier climbers liked summits ____c__ had never been climbed before.A which b which they c that they d unless they 6 _____d_ single aim was getting to the topA they're b there c their d theirs7 ___a___ Zermatt and Chamonix,most places were unknown.A except b unless c without d apart from8 ____b__ were generally dirty and flea-ridden.A the few inns that existed b inns like this C such inns d few innsLesson 45 several cases have been reported in Russia recently of people ____b__ can readA whom b that c which d they 6 one day she came into his office and put her hands on the door of the safe ____c__ A as it happened b by chance c perhaps d intentionally7 _d_____ these tests were being conducted ,she was able to read a newspaper.A during b on occasion c while d as if8 Vera couldn't see with her skin ____a__ she was blindfold .A only b except c as if d unlessLesson 55 the problem,if there is one, __d____ by older peopleA created b is created c creates d is creating6 for one thing ,if you ___a___ a problem,you have a certain identity.A were b being c had d are 7 ____c__ to be linked with life ,and the origin of things.A they seem b it seems c this seems d what seems 8 it is ___b___ they are conceited and ill-manneredA necessary b permissible c possible d likely Lesson 65 if only ____a_ possible for the common people to meet each other.A it would be b it could be c it were d it might be 6 you play __a__ win A in order to b in order that c so that d for 7 the village green is the _a__ you pick sides.A the place b the time c the reason d the cause8 ____d__ the question of national prestige arisesA the moment b just c as long as d provedingLesson 75 not __b____ sound made by animals serves as languageA every b each c the whole d the entire6 we have only to turn to that extraordinary discovery of echo-location in bats to see a case ____a__ the voice plays a strictly utilitarian roleA which b where c when d though7 __c____ he shout in the vicinity of a wall, an echo will come back.A should b if c when d though8 ___d___ the echo-sounding apparatus was born.A such b the way c that's how d like thisLesson 8 5 american farmers can't export chickens to europe ___b___ differences in national regulations.A through b according to c in respect of d because of 6 an electric razor from the eu __a____ sold in the us unless it meets us standards.A oughtn't to be b can't be c shouldn't be d doesn't have to be 7 america and the eu ____a__ to reach a deal A are still trying b slways try c tried d were trying8 the details are __b____ that they may be hard-pressed to get a deal.A so complex b enough complex c such complexity d too complex。