Q1: a number of 與 the number of 有什麼區別?
Q2: amount of，number of ，quantity of 有什麼區別?
1. A number of + 複數名詞 + 複數動詞
=some/或a lot of + 複數名詞 + 複數動詞
A number of people have protested the actions of the Philippine government.
Some/A lot of people have protested the actions of the Philippine government.
2. The number of + 複數名詞 + 單數動詞
The number of people in this nation has grown.
The number of cars in this city is greater than the number of parking spaces available.
1. amount 通常跟不可數 (uncountable)、無生命 (inanimate) 的名詞連用
-The amount of stress I have to suffer during finals week is immeasurable (mostly because I did not study until the last week).
-My wife did NOT spent a very large amount of money yesterday. She only spent 100 NTD, which was all the money I had in my wallet.
2. number 跟可數 (countable)、有生命 (animate) 或無生命 (inanimate) 的名詞連用
-Only a small number of people were infected with the H7N9 strain of the bird flu.
-The president of (fill in the nation of your choice) has made a large number of mistakes.
3. quantity 通常跟可數或不可數、無生命的名詞連用
-There are large quantities of apples on sale in the market.
-A large quantity of imported beer has been sold.