首页
登录
职称英语
[originaltext] Today, most countries in the world have canals. Even in the 2
[originaltext] Today, most countries in the world have canals. Even in the 2
游客
2023-09-12
65
管理
问题
Today, most countries in the world have canals. Even in the 20th century, goods can be moved more cheaply by boat that any other means of transport. Some canals such as the Suez or the Panama, save ships weeks of time by making their voyage a thousand miles shorter. Other canals permit boats to reach cities that are not located on the coast. Still other canals drain lands where there is too much water, help to irrigate fields where there is not enough water.
In places where it does not rain very often, irrigation canals drain water from rivers or lakes such as the lake behind the Aswan Dam on the Nile River, and provide the irrigation water.
In places where there is too much water, canals can drain the water off the land for use in fanning. In Holland, acres and acres of land have been drained in this way. Since much of this drained land is below sea level, the water in the canals has to be pumped up to sea level. Dikes have been built in Holland to keep the sea from covering the land, as it did in the past.
Canals are also used to carry water to mills and factories. The water from a river is kept at a higher level than the river until it reaches the wheel of the mill. Then the water is poured over un61 it reaches the wheel of the mill. Then the water is poured over the mill wheel, making it turn. The same principle is used in more modern factories and in hydroelectric generating plants. The force of the water, falling from a certain height, provides a cheap way of producing electricity.
选项
A、Navigation.
B、Drainage.
C、Irrigation.
D、Electricity.
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3006984.html
相关试题推荐
[originaltext]WhenpeterandRosecametotheUnitedStatesfromthePhilip
[originaltext]Todayschoolchildreninmanycountrieshavehighratesoffa
[originaltext]Todayschoolchildreninmanycountrieshavehighratesoffa
[originaltext]Todayschoolchildreninmanycountrieshavehighratesoffa
[originaltext]Aftertravelinginacrowdedbusandwaitinginthenoisyair
[originaltext]W:Hi,Sam,IhatetobotheryoubutIwonderifIcouldhaveaw
[originaltext]W:Howdoyoufindyournewapartment?M:Well,it’squitenicere
[originaltext]W:Howdoyoufindyournewapartment?M:Well,it’squitenicere
[originaltext]W:Howdoyoufindyournewapartment?M:Well,it’squitenicere
[originaltext]W:Howdoyoufindyournewapartment?M:Well,it’squitenicere
随机试题
[originaltext]W:Hi,howiseverything?Areyoureadyfortheparty?M:Yes,ju
下列辅酶中的哪个不是来自于维生素?( )A.CoA B.CoQ C.PLP
关于卖出看跌期权,以下说法中正确的是()。(不考虑交易费用)A、卖方履约成为多
题目:低年级《动物与我们同行》教学 ?2.内容: 以动物为主题的艺术欣赏与评
患者,男性,45岁。尿潴留,遵医嘱行留置导尿术。插尿管时应提起阴茎与腹壁成60°
对伤口局部进行热湿敷时,应特别注意A.防止弄湿床单 B.皮肤局部及周边涂抹凡士
《变电验收管理规定第22分册站用变验收细则》:油浸式站用变竣工(预)验收站用变铁
根据下列资料回答问题。 2009年1-3月,入境旅游的日本游客人数约为(
下列车船中,属于减半征收车船税的是()。A.警用车船 B.临时入境的外国车船
一段时间内所有盈利交易的总盈利额与同时段所有亏损交易的总亏损额的比值称为( )
最新回复
(
0
)