文勇的新托福黄金&ccedil

Essentialinformationinthe

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Unformatted text preview: below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information ○ Because physical and chemical properties of substances are unchanging, they are useful records of climate 313 [email protected] 在在在在在在 www.liuwenyong.com 在在在在在在在在在在在在在在在,在在在在在在在在在在 fluctuations over time ○ For hundreds or thousands of years, people have been observing changes in the chemical and physical properties of substances in order to infer climate change ○ Because it takes long periods of time for the climate to change, systematic changes in the properties of substances are difficult to observe. ○ Changes in systematically deposited substances that are affected by climate can indicate climate variations over time. 4. According to paragraph 3, scientists are able to reconstruct proxy temperature records by ○ studying regional differences in temperature variations ○ studying and dating changes in the properties of substances ○ observing changes in present day climate conditions ○ inferring past climate shifts from observations of current climatic changes Paragraph 4在What the proxy records make abundantly clear is that there have been significant natural changes in the climate over timescales longer than a few thousand years. Equally striking however, is the relative stability , of the climate in the past 10.000 years (the Holocene period). 5. The word striking in the passage is closest in meaning to ○ noticeable ○ confusing ○ true ○ unlikely Paragraph 3在Over long periods of time, substances whose physical and chemical properties change with the ambient climate at the time can be deposited in a systematic way to provide a continuous record of changes in those properties overtime, sometimes for hundreds or thousands of years. Generally, the layering occurs on an annual basis, hence the observed changes in the records can be dated. Information on temperature, rainfall, and other aspects of the climate that can be inferred from the systematic changes in properties is usually referred to as proxy data. Proxy temperature records have been reconstructed from ice core drilled out of the central Greenland ice cap, calcite shells embedded in layered lake sediments in Western Europe, ocean floor sediment cores from the tropical Atlantic Ocean, ice cores from Peruvian glaciers, and ice cores from eastern Antarctica. While these records provide broadly consistent indications that temperature variations can occur on a global scale, there are nonetheless some intriguing differences, which suggest that the pattern of temperature variations in regional climates can also differ significantly from each other. Paragraph 4在What the proxy records make abundantly clear is that there have been significant natural changes in the climate over timescales longer than a few thousand years. Equally striking, however, is the relative stability of the climate in the past 10.000 years (the Holocene period). 6. According to paragraphs 3 and 4,...
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This note was uploaded on 09/17/2013 for the course LANGUAGE 13DL208 taught by Professor Wang during the Fall '13 term at East China Normal University.

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