Amount và Amounts
amount: An amount of something is how much of it you have, need, or get.
They measured the amount of salt lost in sweat.
I was horrified by the amount of work I had to do.
You can talk about a large amount or a small amount. Don't talk about a 'big amount' or a 'little amount'.
Use only a small amount of water at first.
The army gave out large amounts of food.
When you use amount in the plural, you use a plural verb with it. For example, you say 'Large amounts of money werewasted'. Don't say 'Large amounts of money was wasted'.
Increasing amounts of force are necessary.
Very large amounts of money are required.Be Careful!
Don't talk about an 'amount' of things or people. For example, don't say 'There was an amount of chairs in the room'. You say'There were a number of chairs in the room'. When you use number like this, you use a plural verb with it.
A number of offers were received.
http://www.thefreedictionary.com/amount