英語四級閲讀單項模擬訓練題附答案
To struggle in sweat pooled rivers, will cause the boat to the other side of the ideal sail.以下是小編為大家搜索整理英語四級閲讀單項模擬訓練題附答案,希望能給大家帶來幫助!更多精彩內容請及時關注我們應屆畢業生考試網!
When we analyze the salt salinity(鹽濃度) of ocean waters, we find that it varies 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. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted (稀釋) 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.
Normally, in hot 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, the densest water in the ocean 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 portion of the oceans of the world.
26. This passage mainly tells us about_______.
A. the analysis of the salinity of ocean waters
B. the causes of the variation in oceanic salinity
C. the importance of the changes in oceanic salinity
D. the different forms of salts in ocean waters
can be known from the passage that increase in the salinity of ocean water is caused by______.
A. melting of sea ice B. precipitation
C. evaporation D. supplement of salt
h of the following is not the cause of the decrease in the oceanic salinity?
A. Precipitation. B. Rain and snow.
C. Formation of ice. D. Addition of water by rivers.
h of the following statements is TRUE according to the passage?
A. Oceanic salinity has great effect on sea life.
B. Many factors combine to cause changes in oceanic salinity.
C. The movement of the water is related to the amount of salt.
D. The temperature of the water has much to do with the oceanic salinity.
purpose of mentioning the Weddell Sea is_______.
A. to give an example of cold-water salinity
B. to point out the location of deep waters
C. to make a comparison between hot-water salinity and cold-water salinity
D. to show that the water in the Weddell Sea varies in salinity from place to place
參考答案:
26. B 27. C 28. C 29. D 30. A
更多英語四級考試相關試題推薦:
1.2017年英語四級段落匹配真題演練
2.2017年英語四級快速閲讀練習題
3.2017年英語四級考試提分試卷
4.2017年英語四級閲讀理解考試題及答案解析
5.2017年6月英語四級翻譯考試預測試題
6.2017年英語四級考試備考提分訓練
7.英語四級閲讀提分練習題2017年備考
8.關於2017春節的大學英語四級翻譯練習題
9.2017年6月英語四級考試完形填空練習題及答案
10.2017大學英語四級仔細閲讀練習題
-
2023年6月英語四級詞彙185個
大學英語四級詞彙量比較大,考生要注意這方面的詞彙量的積累。以下是小編為大家收集的2023年6月英語四級詞彙,歡迎閲讀,希望大家能夠喜歡。1、faultya.有錯誤的,有缺點的2、favorablea.稱讚道;有利的,順利的3、favoritea.特別受喜歡的n.喜愛的人或物4、galleryn.畫廊...
-
2022下半年英語四級模擬試卷及答案
2022年下半年英語四級考試將在12月17日開考,大家要抓緊時間複習。下面是小編提供給大家關於下半年英語四級模擬試卷及答案相關內容,希望同學們認真練習。PartⅡReadingComprehension(35minutes)Directions:Thereare4passagesinthispart.Eachpassageisfollowedbys...
-
英語四級作文:乾渴的世界(A Thirsty World)
在平平淡淡的日常中,大家都接觸過作文吧,藉助作文可以宣泄心中的情感,調節自己的.心情。你寫作文時總是無從下筆?下面是小編收集整理的英語四級作文:乾渴的世界(AThirstyWorld),歡迎閲讀,希望大家能夠喜歡。theworldisnotonlyhungry,itisalsothirsty.thismaysoundstra...
-
2022年英語四級作文萬能句子大全
在日復一日的學習、工作或生活中,大家一定都接觸過作文吧,作文可分為國小作文、中學作文、大學作文(論文)。那麼,怎麼去寫作文呢?以下是小編收集整理的2022年英語四級作文萬能句子大全,歡迎閲讀與收藏。英語四級作文萬能句子1gwiththeadvanceofthesocietymoreandmorep...