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    12月英語六級完形填空練習及答案

    時間:2021-02-01 19:11:14 英語六級

    2017年12月英語六級完形填空練習及答案

      英語是現在世界上用的最多的`一門語言,許多國家都在學英語和用英語,所以,學好了英語,出門就不怕溝通不方便了。下面是小編為大家搜索整理的英語六級輔導訓練,希望能給大家帶來幫助!

    2017年12月英語六級完形填空練習及答案

      Leonardo da Vinci was the first man to suggest that growing trees add a new ring in their trunks each year. The 11 in these rings relates to the physical conditions which the tree experiences. Thus, trees grown in a 12 area and time each develop a pattern or configuration of their rings.

      This 13 was of little significance until Andrew E. Douglas began to study tree rings in Arizona in 1900. Using a technique called cross dating, he was able to employ tree rings to the study of archaeological sites and date the ruins with 14 . Some were as old as 6700 B. C. ! This study of tree rings is called dendrochronology.

      In time the cross dating was 15 by a carbon 14 process. This approach measured the amount of carbon 14 radiating from a piece of wood and 16 to determine the age of that wood. Further use of the carbon 14 technique has shown that the radiation process is more complex and less 17 than had been at first thought.

      The most 18 aspect of tree ring research is now called

      dendroclimatology. This 19 of the reconstruction of climates and climatic cycles and events from the evidence found in the tree rings. From this it is hoped that a 20 of drought cycles can be determined in the American Southwest. Such information will be of great help in determining the life and ecology of that region of the United States.

      A. thus

      B. model

      C. variation

      D. concept

      E. accuracy

      F. exciting

      G. consists

      H. given

      I. proposition

      J. composes

      K. further

      L. pattern

      M. supplemented

      N. reliable

      O. excellent

      參考答案

      11. C 12. H 13. D 14. E 15. M 16. A 17. N 18. F 19. G 20. L

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