2019年托福考试阅读考前必做试题6

阅读试题中国考生来说并不是特别的难，但是要想获得高分也不是件容易的事，需要我们在备考的时候多做写模拟题，今天小编就给大家准备了这篇模拟题，在坦途网托福考试频道还有很多新的内容，现在我们先来看看这篇文章吧！

If the salinity of ocean waters is analyzed, it is found to vary only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation —— conversion of liquid water to water vapor. In this manner, the salinity is increased, since the salts stay behind. If this is carried to the extreme, of course, white crystals of salt would be left behind.

The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by evaporation, or decreased by the addition of fresh water by precipitation or runoff.

Normally, in tropical regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.

A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.

In the Weddell Sea, off Antarctica, the densest water in the oceans is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portions of the oceans of the world.

4l. What does the passage mainly discuss?

(A) The elements of salt

(B) The bodies of water of the world

(C) The many forms of ocean life

(D) The salinity of ocean water

42. The word "this" in line 5 refers to

(A) ocean

(B) evaporation

(C) salinity

(D) crystals

43. According to the passage, the ocean generally has more salt in

(A) coastal areas

(B) tropical areas

(C) rainy areas

(D) turbulent areas

44. All of the following are processes that decrease salinity EXCEPT

(A) evaporation

(B) precipitation

(C) runoff

(D) melting

这就是这篇文章的全部内容了，我们在阅读的时候，可以不仅仅是做题，我们还可以在文章中摘抄一些比较优秀的句子作为写作素材，一举两得，小编会持续为大家更新很多相关的内容，做好每月托福考试时间的变更，希望能够帮助正在努力复习的小伙伴们！