EI NIno is name given to the masterious and often unpredictable change in the climate of the world.This strange ___1_____happens every five to eight years.It starts in the PAacific Ocean and is thought to be caused by a failure in the trade winds(信風(fēng))，which affects the ocean currents driven by these winds. As the trade winds lessen in ____2____,the ocean comperatures rise causing the Peru current flowing in form 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 ___3___thunderstorms.The rainfall is increased acrossAounth American ____4____floods to Peru.In the West pacific,there are droughts affecting Australia and Indonesia.So while some parts of the world perpare for heavy rains and floods,other parts face drought,poor crops and____5____. 　　EI Nino usually lasts for about 18 months The 1982-83 EI Nino brough the most___6____weather in mordern history .Its effect was worldwide and it left more than 2,000 people dead and caused over eight billion pounds ____7___of damage.The 1990 EI Nino will ____9___,but they are still not __10___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

答案解析

　　1. P phenomenon 　　2. B strength 　　3. E tropical 　　4. L bringing 　　5. K starvation 　　6. J destructive 　　7. N worth 　　8. A estimate 　　9. O strike 　　10. I completely