有请高手现身解答：请问number、quantity和amount 有什么区别？（希望具体点的答案）

a great number of+可数名词复数，
如：I have a large number of books.
a large amount of/amounts of + 单数名词，
如：We need amounts of money to buy the house.
a great deal of+单数名词，A great deal of time is needed.
a large quantity of+ 可数名词复数/不可数名词，
如：A large quantity of students are planting trees in the park.
A large quantity of water is needed in th ehot summer.
但quantities of 作主语时，谓语要用复数，如：
Quantities of water are needed in hot summer.

a large number of 修饰可数名词复数, singular verb
a large amount of 修饰不可数名词, plural verb
a great deal of 修饰不可数名词, plural verb
a large sum of 修饰不可数名词, plural verb

还有，英语多用 a great deal of ，而不是a large deal of 。
首先要搞清楚，是修饰可数名词或不可数名词，而不是单数或复数名词。可数名词都有复数形式，而不可数名词没有复数形式。
a large deal of、a plenty of和a good supply of 在多数情况下修饰不可数名词，如：a plenty of water, a geat deal of time，不过它们也可以修饰可数名词，如a plenty of men。
a quantity of在多数情况下修饰可数名词，如a quantity of boxes, 不过也可修饰不可数名词，如a quantity of milk。