表示可从前文找相应线索的有两类。
与this一大类的还有：This/these/such; the same/similar; worse/better/more/less等。
还有就是表示逻辑关系的句间连词，或者叫连接副词。主要的如下。
递进：Moreover/furthermore/what’more/besides/in addition/even/also
转折：however/but/rather/instead
因果：therefore/consequently/accordingly/thus/hence
3.后文(总分)
El Nino usually lasts for about 18 months. The 1981-83 El Nino brought the most 52 weather in modern history. Its effect was worldwide and it left more than 2,000 people dead and caused over eight billion pounds 53 of damage.
段落开始部分，提出一个总的概括性的说法。往往在下文有分述。El Nino究竟带来的是什么样的天气，后面一句就交代得十分清楚。
三看习惯用法：固定搭配
Its effect was worldwide and it left more than 2,000 people dead and caused over eight billion pounds 53 of damage.
此处考的是worth这个词的特殊用法。它本是一个形容词，但可用？worth of sth, 来表明价值某物的某东西。
III.总结
选择填空考的是猜测词义的能力，其核心在于通过各种线索来确定词性和意义，从而实现成功匹配。解题方法也相应产生。
先通过词的后缀等对选项进行合理的分类，分不出的可先模糊处理。
再通过文章逐一确定空格所需要的词性和意义。它需要看句子中此词所处的位置，它的周边环境。
有时甚至需要跳出此句，看前文或后文。如指代词/句间连词告诉我们要向前寻找；而段首的抽象表达可能要从下文找到钥匙。
附一：四级常用后缀
1. 名词后缀
1)-or/er/ess/crat/cis:做某件事情或职业的人或物：worker, debtor
2)-acy, 表示"性质，状态，境遇" democracy, accuracy, diplomacy
3)-ance, -ence表示"性质，状况，行为，过程，总量，程度” importance, diligence, difference, obedience
4)-ancy, -ency, 表示"性质，状态，行为，过程" frequency, urgency, efficiency,
5)-bility, 表示"动作，性质，状态" possibility, flexibility, feasibility,
6)-dom, 表示"等级，领域，状态" freedom, kingdom, wisdom
7)-hood, 表示"资格，身份, 年纪，状态" childhood, manhood, falsehood
8)-ion, -sion, -tion, -ation, -ition, 表示"行为的过程，结果，状况" action, solution, conclusion, destruction, expression, correction
9)-ism, 表示"制度，主义，学说，信仰，行为" socialism, criticism, colloquialism, heroism
10)-ity, 表示"性质，状态，程度” purity, reality, ability, calamity
11)-ment, 表示"行为，状态，过程，手段及其结果 treatment, movement, judgment, punishment, argument
12)-ness, 表示"性质，状态，程度" goodness, kindness, tiredness, friendliness
13)-ship, 表示"情况，性质，技巧，技能及身份，职业” hardship, membership, friendship
14)-th, 表示"动作，性质，过程，状态" depth, wealth, truth, length, growth
15)-tude, 表示"性质，状态，程度" latitude, altitude(海拔)
16)-ure, 表示"行为，结果" exposure, pressure, failure, procedure(手续)，
17-grapy, 表示"……学，写法” biography, calligraphy, geography
18)-ic, ics, 表示"……学……法" logic, mechanics, electronics, linguistics
19)-ology, 表示"……学……论”biology, zoology, technology(工艺学)
20)-nomy, 表示"……学……术" astronomy, economy, bionomy(生态学)
2. 形容词后缀
(1)带有“属性，倾向，相关”的含义
1)-able, -ible, visible, flexible
2)名词-ish, foolish, bookish, selfish(注意accomplish, vanish)
3)-ive, active, sensitive, productive
4)-like, manlike, childlike
5)名词-ly, manly, fatherly, scholarly, motherly
6)-some, troublesome, handsome
7)-ful, beautiful, wonderful, helpful, truthful
8)-ous, dangerous, generous, courageous, various
9)-ent, violent
10)-most, foremost, topmost
(11)less, 表示否定，countless, stainless, wireless
3. 动词后缀
1)-ize, ise, 表示"做成，变成，……化“modernize, mechanize, democratize, organize
2)-en, 表示"使成为，引起，使有” quicken, weaken, soften, harden
3)-fy, 表示"使……化, 使成”beautify, purify, intensify, signify, simplify
4)-ish, 表示"使，令” finish, abolish, diminish, establish
5)-ate, 表示“成为……，处理，作用” separate, operate, indicate
4. 副词后缀
(形容词)-ly：bad→badly坏地/恶劣地，careful→carefully小心地
-wise(OE)：clock→clockwise(a./adv.)顺时针方向的(地)；like→likewise同样地
-wards：out→outwards向外面地，north→northwards向北方地
附二：真题及参考答案
El Nino is the name given to the mysterious and often unpredictable change in the climate of the world. This strange 47 happens every five to eight years.
It starts in the Pacific Ocean and is thought to be caused by a failure in the trade winds(信风), which affects the ocean currents driven by these winds. As the trade winds lessen in 48 , the ocean temperatures rise, causing the Peru current flowing in from the east to warm up by as much as 5 °C.
The warming of the ocean has far-reaching effects. The hot, humid (潮湿的) air over the ocean causes severe 49 thunderstorms. The rainfall is increased across South America, 50 floods to Peru. In the West Pacific, there are droughts affecting Australia and Indonesia. So while some parts of the world prepare for heavy rains and floods, other parts face drought, poor crops and 51.
El Nino usually lasts for about 18 months. The 1981-83 El Nino brought the most 52 weather in modern history. Its effect was worldwide and it left more than 2,000 people dead and caused over eight billion pounds 53 of damage. The 1990 El Nino lasted until June 1995. Scientists 54 this to be the longest El Nino for 2,000 years.
Nowadays, weather experts are able to forecast when an El Nino will 55 , but they are still not 56 sure what leads to it or what affects how strong it will be.
A) estimate
B) strength
C) deliberately
D) notify
E) tropical
F) phenomenon
G) stable
H) attraction
I) completely
J) destructive
K) starvation
L) bringing
M) exhaustion
N) worth
O) strike
参考答案：
47. P phenomenon
48. B strength
49. E tropical
50. L bringing
51. K starvation
52. J destructive
53. N worth
54. A estimate
55. O strike
56. I completely
