2013年新托福考试:toefl阅读出题点分析
(1)如TPO中的这道细节题 Paragraph 2:During wakefulness, breathing is controlled by two interacting systems. The first is an automatic, metabolic system whose control is centered in the brain stem. It subconsciously adjusts breathing rate and depth in order to regulate the levels of carbon dioxide (C02,) and oxygen (02,), and the acid-base ratio in the blood. The second system is the voluntary, behavioral system. Its control center is based in the forebrain, and it regulates breathing for use in speech, singing, sighing, and so on. It is capable o... [ 查看全文 ]2013年新托福考试:toefl阅读出题点分析的相关文章
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