I will try to succeed on the TOEFL-Test in 6 days and therefore I would appreciate you to proofread some of my essays.
So here is the first one about a special types of winds, called "jet streams", who had been discussed in a passage and lecture.
" In the passage and lecture a special type of winds, called “jet streams” is described.
A jet stream is a hard blowing wind, due to temperature gradients between the warmth in the troposphere and the heat on earth's surface. The strength of such a stream is normally a direct cause to the intensity of temperature differences. Winds were classified as jet streams at a speed above 57 miles per hour, but some even reach 300 miles per hour.
In the area between the equator and north pole, there were two main patterns of stream winds classified. The subtropical stream is found in the south of the United States. In Idaho and Mantana the polar jet stream occurs. According to the lecture, this stream sometimes expands even to Texas, when it is a cold winter in the US.
The power of some jet streams have an enormous effect on traveling by plane. As the professor puts it, flying against the direction of a jet stream can cause an airplane to need more time to arrive at its goal. The delay reaches even a few hours sometimes. Moreover, the wind blowing at the front of the plane increases the need of fuel and can lead to turbulances."