託福閱讀推理題中如何找準推理依據
在託福閱讀十大經典題型中，推理題的難度排行僅次於文章內容小結題，往往是令考生們聞之色變的一道難題。要提高推理題的解題正確率，首要前提就是要能夠準確找到該題的推理依據。下面結合例題我們分享一下在解答推理題時，如何準確找到推理依據。
推理依據來自何處呢?當然是原文。那麼又如何從茫茫詞海中找到這一依據呢?根據題幹。解題的時候，題幹就像茫茫大海中的一座燈塔，往往會爲我們指引正確的方向。因此，完成閱讀推理題我們應該——步驟一，審題。通過審題，確定本題的推理對象。步驟二，回原文中鎖定推理對象的位置。如果推理對象存在於原文某個句子中的其中一個分句或一個部分，則推理依據就在本句剩下的內容中;如果推理對象存在於原文一個完整的句子中，則推理依據需要結合上下文。
實例解析：(TPO24)
By whatever means, a lake is constantly gaining water and losing water: its water does not just sit there, or, anyway, not for long. This raises the matter of a lake’s residence time. The residence time is the average length of time that any particular molecule of water remains in the lake, and it is calculated by dividing the volume of water in the lake by the rate at which water leaves the lake. The residence time is an average; the time spent in the lake by a given molecule (if we could follow its fate) would depend on the route it took: it might flow through as part of the fastest, most direct current, or it might circle in a backwater for an indefinitely long time.
It can be inferred from paragraph 4 that the length of time a given molecule of water remains in a lake
A. depends entirely upon the average speed of a lake' s currents
B. can be measured by the volume of the lake alone
C. can be greater or lesser than the residence time
D. is similar to the length of time all other molecules remain in that lake
解題具體步驟：
1)首先審題，我們知道推理對象爲the length of time a given molecule of water remains in a lake;
2)然後通過定位，找到原文包含推理對象的句子，即原文最後一句話的後半句，“The residence time is an average; the time spent in the lake by a given molecule (if we could follow its fate) would depend on the route it took: it might flow through as part of the fastest, most direct current, or it might circle in a backwater for an indefinitely long time.”
3)本句話以分號分成了前後兩個分句，因此前一個分句也需要分析。前一個分句，即“The residence time is an average，停留時間是平均的”，這個信息點需要記住;
4)接下來再把後半句看完。後半句，即“the time spent in the lake by a given molecule would depend on the route it took，一分子的水停留在湖裏的時間取決於它所走的路線”，隱含意思即水停留在湖裏的時間是不固定的，走的路線是直線，則停留時間短，走的路線是循環的，則停留時間就長;
5)結合前一個分句，可得出結論，一分子的水停留在湖裏的時間可能比residence time 長，也可能比它短，故答案爲C。
通過講解上述例題，相信考生們能夠把握推理依據的方向，簡而言之，包含推理對象的句子是完整的，則結合上下文尋找推理依據;如果包含推理對象的句子是不完整的，則推理依據蘊藏在本句中。
