很多人都抱怨PTE考试有些难，其实主要原因还是没有好好进行PTE培训，经过系统的教导后，相信你的PTE写作、PTE阅读、PTE词汇、PTE口语、PTE听力能力都能提高一个档次。今天小编想给大家呈现这些内容。

　　RO：

　　A、Theyare caused by great temperature differences between adjacent air masses. There are four major jet streams.

　　B、Sincethe progress of an airplane is aided or impeded depending on whether tail windsorhead winds are encountered.

　　C、Insteadof moving along a straight line, the jet stream flows in a wavelike fashion;the wavespropagate eastward (in the Northern Hemisphere) at speeds considerably slower than the wind speed itself.

　　D、Jetstream, narrow, swift currents or tubes of air found at heights ranging from 7to 8 mi(11.3–12.9 km) above the surface of the earth.

　　E、In the Northern Hemisphere the jet stream issought by eastbound aircraft, in order to gain speed and savefuel, and avoided by westbound aircraft.

　　SWT：

　　Theco-evolutionary relationship between cows and grass is one of nature'sunderappreciated wonders; it also happens to be the key to understanding justabout everything about modern meat.

　　For the grasses,which have evolved to withstand the grazing of ruminants, the cow maintains andexpands their habitat by preventing trees and shrubs from gaining a foothold andhogging the sunlight; the animal also spreads grass seed, plants it with hishooves, and then fertilizes it with his manure.

　　In exchange for these services the grasses offerruminants a plentiful and exclusive supply of lunch. For cows (like sheep, bison,and other ruminants) have evolved the special ability to convert grass— whichsingle-stomached creatures like us can't digest—into high-quality protein. Theycan do this because they possess what is surely the most highly evolveddigestive organ in nature: the rumen. About the size of a medicine ball, theorgan is essentially a forty-five-gallon fermentation tank in which a residentpopulation of bacteria dines on grass.

　　PTE考试网一直致力于做PTE培训，现在PTE考试需要有优秀的老师去辅导上课，感兴趣的学生可以咨询我们哦!如果你对PTE英语考试官方指南、PTE是机考吗等信息感兴趣。可以直接联系我们。