课前作业句子插入-强化

1、虾说阅读: 托福阅读 10 大解题思路 强化课句子题判断文以及上下文 之间的: 代词, 关系(词)1Scientists have known for some timet certain plants, called hyper accumulators,can concentrate mineralsevels adredfoldreatern normal. A surveyof known hyper accumulators identifiedt 75 percent of them amassed nickel; cobalt,copper, zinc, manga, lead,

2、 and cadmium are other minerals of choice. Hyperaccumulators run the entire range of the plant world. They may be herbs, shrubs, or trees . Many members of the mustard family, spurge family, legume family, andgrass family are top hyper accumulators. Many are foundropical and subtropicalareas of the

3、world, where accumulation of high concentrations of metals may afford some protection against plant-eating insects and microbial pathogens.Certain minerals are more likely to be accumulated in large others.ties2Pacific islanders are variously thought to have come from Normerica, SouthAmerica, Egypt,

4、 Israel, and, as well as Southeast Asia. Many older theoriesimplicitly deprecated the navigational abilities and overall cultural creativity of thePacific islanders. For exle, British anthropologists G. Elliot Smind W. J.Perry amedt only Egyptians would have been skilled enough to navigate andcoloni

5、ze the Pacific . They inferredt the Egyptians even crossed the Pacific tofound the great civilizations of the New World (Nornd Soumerica). In 1947Norwegian adventurer Thor Heyerdahl drifted on a balsa-log raft westward with thewinds and currents across the Pacific from Soumerica to prove his theoryt

6、Pacific islanders were Native Americans (also called Americanns). LaterHeyerdahl suggestedt the Pacific was peopled by three migrations: by NativeAmericans from the Pacific Northwest of Normerica drifting to Hawaii, by Peruviansdrifting to Easter Island, and by Melanesians.Later theories concentrate

7、 on journeyshe other direction.13Onereion regarding the absence of fossils during this important 100-million-year period ist early animals were soft bodied and simply did not fossilize. Fossilization of soft-bodied animals is less likelyn fossilization of hard-bodiedanimals, but it does occur. Condi

8、tionst promote fossilization of soft-bodiedanimals include very ra discouragescovering by sedimentst create an environmenttition. In fact, fossil beds containing soft-bodied animals havebeen known for many years. It is relatively rare because the fossilization of soft-bodied animals requires asperon

9、ment.4 Wattsengine soon showed what it could do . It liberated industry fromdependence on running water. The engine eliminated waterhe mines by drivingefficient pumps, whiadesible deeper and deeper mining. The readyavailability of coal inspired William Murdoch during the 1790s to develop thenewform

10、of nighttime illumination to be discovered in a millennium and a half. Coal gasrivaled smoky oil ls and flickering candles, and earlyhe new century, well-to-doLondoners grew accustomed to gaslit houses and even streets. Iron manufacturers which had starved for fuel while depending on charcoal also b

11、enefited from ever-increasings of coal; blast furnawith-ered bellows turned outmore iron and steel for the new machinery.became the motive force of theIndustrial Revolution as coal and iron ore were the raw materials.The factories did not have to go to the streams when factorieser could come to the5

12、Not only could Smith identify rock strata by the fossils they contained, he could alsosee a pattern emerging: certain fossils always appearore ancient sediments, whileothers bego be seen as the stratae more recent . By following the fossils,Smith was able to put all the strata of Englands eartho rel

13、ative temporal sequence. About the same time, Gees Cuvier made the same discovery while studying therocks around Paris. Soon it was realizedt this principle ounal (animal)sucwas valid not only in England or France but virtually everywhere. It wasactually a principle of floral sucas well, because pla

14、nts showed the sametransformation through time as did fauna. Limestone may be foundhe Cambrian or300 million years laterhe Jurassic strata burilobite the ubiquitous marinearthropod a dinosaurd its birthhe Cambrian will never be found in Jurassic strata, norhe Cambrian.The findings of these geologist

15、s inspired others to examine the rock and fossil records in different parts of the world.26 Another task for the Glomar Challengers scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor. These structures had been detected years earr by ec

16、ho-sounding instruments, butthey had never been penetrated as are common along the United She course of drilling. Were they saomeches Gulf Coast, and if so, why should there havebeen so much solid crystalline salt beneath the floor of the Mediterranean? Thus, scientists had information about the sho

17、f the domes but not abouttheir chemical comition and origin.7Modern attitudes to Roman civilization range from the infiniy impressed to thethorough disgusted. As always, there are theer worshippers , espelly amonghistorians, who are predised to admire whatever is strong, who feel more attractedto th

18、e might of Rome solid body of opinionn to the subtlety of Greece. At the same time, there is at dislikes Rome. For many, Rome is at best the imior andthe continuator of Greece on a larger scale. Greek civilization had quality; Rome,mere Suchty. Greece was the inventor; Rome, the research and develop

19、ment divi.was the opinion of some of the moreellectual Romans. “had the Greeksheld novelty in such disdain as we, ” asked Horace in his date would now exist?”stle, “what work of ancientThey esteem symbols of Romaner, such as the massive Colosseum.8The diffuof agriculture and later of iron waspanied

20、by a great movement ofpeople who may have carried these innovations. These people probably originated ineastern Nigeria. Their migration may have been setotion by an increase inpopulation caused by a movement of peoples fleeing the desiccation, or drying up, of the Sahara. They spoke a language, pri

21、or-Bantu (“Bantu” means “the people”), which is the parent tongue of a language of a large number of Bantu languages stillspoken throughout sub-Sahara Africa. Why and how these people spread outot theircentral and southern Africa remains a mystery , but archaeologists beveiron weapons allowed them t

22、o conquer theirting-gathering opponents, who stillused stone implements. Still, the pros is uncertain, and peaceful migration orsimply rademographic growth may have also caused the Bantu explo. These people had a significant linguistic impact on the continent as well.39Helthis group of teachers to r

23、evise their thinking abolassroom events becamecentral . This pros took time and patience and effective trainers. Theresearchers estimate objectively took bett the initial training of the same teachers to view eventsn 20 and 30 hours, with the samber of hours again beingrequired to practice the skill

24、s of reflection. Wildman and Niles identify three principlest facilie reflective practice in ateaching situation. Theipport from administrators in an education system,enabling teachers to understand the requirements of reflective practice and how itrelates to teaching students. The second is the ava

25、ilability of sufficient time and space.However, changing teachers thinking about reflection will not succeedthere is support for reflectionhe teaching environment.10Lichens helped to speed theition of the hard rock surfa, preparing a softbed of soilt was abundantlyd with mineralsd been carriedhemolten rock from the bowels of Earth. Now, other forms of life could take hold: fernsand