It starts in the Pacific Ocean and is thought to be caused by a failure in the trade winds(信風), 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 (潮濕的) 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

參考答案：

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

此處考的是worth這個詞的特殊用法。它本是一個形容詞，但可用？worth of sth, 來表明價值某物的某東西。

III.總結

選擇填空考的是猜測詞義的能力，其核心在于通過各種線索來確定詞性和意義，從而實現成功匹配。解題方法也相應產生。

先通過詞的后綴等對選項進行合理的分類，分不出的可先模糊處理。

再通過文章逐一確定空格所需要的詞性和意義。它需要看句子中此詞所處的位置，它的周邊環境。

有時甚至需要跳出此句，看前文或后文。如指代詞/句間連詞告訴我們要向前尋找；而段首的抽象表達可能要從下文找到鑰匙。