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PatMoore 《成都信息工程学院学报》2002,17(4):289-299
尽管语法在交际教学法鼎盛时期一度遭到冷遇,但现在又重新被英语语言教学所接纳,作为一种新的语法教学方式,发现原则综合了传统归纳发和演绎法的长处,概述了发现原则的理论依据,指出发现原则旨在鼓励学习者积极参与而非被动接受,符合当前认知主义对二语学习的认识。 相似文献
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The Côte d’Ivoire–Ghana transform margin is bounded to the south by a prominent marginal ridge. ODP Leg 159 shipboard analyses on sediments from four sites document three distinct transform margin sedimentary and tectonic stages of evolution: (1)?an intracontinental stage of transform faulting recorded in deformed lacustrine to marine siliciclastic sequences; (2)?a marginal ridge uplift stage, recorded by shallow water limestones, appears coeval with the passing of a hot, oceanic spreading center just south of the sediment wedge; and (3)?cool ing subsidence of the transform margin recorded in bathyal to abyssal sediments emphasizes a passive margin stage. These results are consistent with previously published models of evolution. 相似文献
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Abstract. Fucus serratus provides a habitable site For much epifauna if conditions are right. Epifaunal colonies in their turn as well Provide habitats in which meiofauna can dwell. Thus micro-environment is provided which is Dependent on colony-species, -size and silt for its riches. Analysis of population data shows the facts are Turbellarian abundance rarely relates to other taxa, However the flatworms' population count Closely relates to total meiofaunal amount. Experiments on bryozoan-choice by Monocelis lineata show This worm prefers Flustrellidra as a place to go. This may in part be due to thigmotactic deference But mainly seems related to a feeding preference. In addition to behaviour towards food and concavity, Responses are shown to light, temperature, current and gravity. In the discussion thus it is partly explained How meiofauna finds epifauna and there is maintained. 相似文献
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Feeding habits of harp and hooded seals in drift ice waters along the east coast of Greenland in summer and winter 总被引:2,自引:0,他引:2
Results of analyses of stomach and intestinal contents from hooded ( Cystophora cristata ) and harp ( Phoca groenlandica ) seals captured in the pack ice belt of the Greenland Sea in summer (July-August) in 2000 and winter (February-March) in 2001 revealed that the diet of both species were comprised of relatively few prey taxa. Pelagic amphipods of the genus Parathemisto , the squid Gonatus fabricii , polar cod ( Boreogadus saida ) and capelin ( Mallotus villosus ) constituted 63-99% of the observed diet biomass in both seal species, irrespective of sampling period, but their relative contribution to the diet varied both with species and sampling period/area. For hooded seals, G. fabricii and capelin were the dominant food items in winter 2001, but the summer 2000 diet comprised a mixture of this squid and polar cod. Parathemisto was most important for the harp seals during summer 2000; in winter 2001 the contribution from krill and capelin were comparable to that of Parathemisto . Multivariate analyses revealed differences in the intestinal contents of hooded and harp seals in areas where the two species' occurrence spatially overlapped. Different foraging depths of the two species may have contributed to the observed differences in diets. 相似文献