1. 因果關系
因：because, because of, for, as, since, in that, on account of, with
果：so, so that, therefore, thereby, as a result, hence, thus, consequently, accordingly
因果關系除了傳統意義上的顯性因果表達詞外，隱性的因果同樣是不可忽略的一個重要部分。
隱性因果：
A 導致(因-果)：cause, reason, lead to, give rise to, result in, render, make, let, ask, support, push, stimulate, spark, spur, fuel, produce, be responsible for
如The increased pressures of expanding populations have led to the removal of woody plants so that many cities and towns are surrounded by large areas completely lacking in trees and shrubs。
在這段話中，有lead to, 表示了導致的意思，即結果; 而so that 更進一步表示了后面的結果，所以可以充分判定這段話有因果關系的邏輯。
B 由…而來(果-因)：result from, derive from, originate from, initiate from, stem from, be responsive to, be attributable to
如 “The extreme seriousness of desertification results from the vast areas of land and tremendous numbers of people affected, as well as from the great difficulty of reversing or even slowing the process。”
在這段話中，根據result from可以推斷出有因果關系，那如果是解釋句子題時，選項中有因果關系就可以優先考慮。
C 反映，體現(果-因)： reflect, present, demonstrate, suggest, imply, show
This result demonstrates that…
D 考慮到： given, considering, in view of, thanks to, according to
He succeeded thanks to (in view of) his effort。
E 依賴于： rely on, depend on, resort to,
He resorted to books when he had problems。
F 條件關系：when, once, as soon as, as long as
As soon as he got the money, he would leave the country at once。
G 分詞短語，不定式做狀語
Failing in the final exam, she cried。
2. 對比轉折關系
A 對比：while, whereas, on the other hand
在解釋句子題，插入句子題中，一旦出現對比關系，學生在掌握的基礎上就能非常快速的判定句間和句內的關系。While, whereas 前后連接的是平行結構，on the other hand前必定有on one hand, 可以用來把握句間關系。
B 轉折：but, although, despite, in spite of, nevertheless, however
轉折是托福閱讀的一個經典考點之一，掌握這些轉折詞對考試非常有幫助。
3. 比較關系
A 同級比較 as…as
B 比較級：more…than, -er than, less…than
C 變化：change, alter, vary, modify, revise, increase, decrease, enhance, diminish, develop, progress, advance, improve, retreat, degenerate, continue, remain
D 差異：different, distinguish, separate, same, similar, comparable, compare…to
E 超越：surpass, exceed, excel, over
F 最高級
1)本身有最高級含義：maximum, minimum, peak, outstanding, top
2) 本身程度比較深：amazing, surprising, astonishing, prohibitively high
3) 否定+比較=最高級
No one is more outstanding than him。
從這句話中可以看出，否定加比較表示的是一種最高級關系。
4. 否定關系
顯性否定：no, not, never, nor, none neither
隱形否定：fail to, refuse, remove, miss, reject, absence of, lack of
否定前綴：a-, ab-, dis-, il-, im-, in-, non- , un-
否定前綴是詞匯題中經常出的一個考點，把握否定前綴可以幫助考生把握一些生詞，依靠否定前綴對選項進行一個排除。
雙重否定;not fail to, not illegal, not uncommon, not unavailable
雙重否定是英文中經常運用的表達方式，由于在平時中文對話中用的很少，隨意對雙重否定的把握就顯得特別的重要。
考生如果能夠把握住這四個邏輯關系，就等于部分掌握了托�？荚嚨男䴔C。最后，祝各位考生考試順利。