我虽然不是老师，但我想谈谈我的看法：

amount就是“数量、总额”的意思，与不可数名词连用。

The amount of water的意思是“水的数量，水量”，that bottle of water的意思是“那瓶水”。

The amount of rain affects the growth of crops.
   雨量影響作物的生長。

The amount of money one makes is not the only gauge of one's success.
   掙錢的多少不是衡量一個人成功的唯一標準。

The amount of money we have is limited.
   我們的錢數額有限。

(1)the amount of water 蓄水量；含水量；产水量

The amount of water collectedin such structure.
蓄水量在此种容器中的水的收集量。

You might say melting ice will add to the amount of water.
你可能会说消融的冰会增加水源的数量。

The amount of water which is suitable to drink is less and less.
适合人类喝的水是越来越少了。

(2)That bott of water =那瓶水，如果要表示那瓶子水有5升，可以这样表达

That bottle of water is 5 litres in volume.

Five litres of water is in that bottle .

(5)the amount of +不可数名词，表示“一定数量.....某物：表示一种抽象不确切概念的数量）

They have only a vague idea of the amount of water available.  

他们只是大概知道可用水的总量。

The amount of sleep we need varies from person to person.  

我们对睡眠的需求量因人而异。

The amount of paperwork involved is mind-boggling.  

相关的书面工作量大得令人难以想象。

I was staggered at the amount of money the ring cost.  

那戒指那么贵，我非常吃惊。

The underlying assumption is that the amount of money available is limited.  

隐含的假定是，可用的资金有限。

(6)the number of +可数名词复数（表示某物的具体数量/数目是多少）(作主语，谓语用单数）

The city has trebled the number of its prisoners to 21,000.  

该市的囚犯人数增长了两倍，达到21,000人。

The number of commuters to London has dropped by 100,000.  

往返于伦敦的上班族减少了10万。

The number of women who become pregnant after adopting children is legion.  

领养小孩后怀孕的妇女比比皆是。

She was intimidated by the number of businessmen buzzing around the saleroom.  

拍卖行里乱哄哄谈生意的商人们令她望而生畏。

The number of independent firms decreased from 198 to 96.  

独立公司的数量从198个减少到了96个

He must limit the number of cigarettes he smokes.
他必须限制他抽烟的数目。

(7)a number of +可数名词复数（表示很多...某物/某人）（作主语，谓语用复数）

A number of very well designed studies have been undertaken.  

已经进行了多项精心规划的研究。

 A number of buildings around the Parliament were still smouldering today.  

国会周围的一些大楼今天还在冒烟。

The bishop conducted a number of confirmations at the service.
主教在仪式上为许多人施行了坚信礼。

A number of cables are needed in this project.
这项工程需要大量电缆。

The Green Party hopes to put up a number of candidates in the General Election.
绿党希望提出若干候选人参加大选。

Quite a number of world famous paintings are on show in this exhibition.
有许多的世界名画在本次展览会上展出。

The play contains a number of typical Stoppard set pieces.
这出戏里有若干典型的斯托帕特式的场景。

A number of soldiers were detached to guard the building.
许多士兵被派去保护这座建筑物。

A number of burglaries have been committed in this area recently.
这一带最近发生了若干起入户盗窃案。

I have consulted a number of law books in the British Museums.
我查阅了大英博物馆里许多法律书籍。

非常感谢老师您的回答，

但正如您的第三个例子

The amount of water which is suitable to drink is less and less.

在这句里翻译成了可以喝的水，指的是水。

bottle在字典里说的也是 一瓶水的量 的意思

那么不能说

A bottle of water is 75 ml.

能不能说

The amount of water is 750 ml.呢？

谢谢您的回答

继续跟踪回答如下

我们不能说 A bottle of water is 75ml.不能用汉语思维来翻译啊！但是你可以说 

A bottle of water is very useful for a person who is very thirsty.

A botthe of water is worth 2 RMB YUAN.

The volume of a bottle of water is 75ml.