Question of 'amount of' & 'number of'

Q1 : As far as I remember, 'amount of' is usually used with uncountable whilst 'number of' is used for plural. Is it correct?

Q2 : In what situation, the 'amount' should be added with 's'?
ex. Large amounts of money were spent. &
He has attracted an enormous amount of public sympathy.

Q3 : which of the following sentences is correct?
Large numbers of vehicles had been towed.
A large number of vehicles had been towed.

I should be most grateful if any persons could teach me!

Q1: Yes. Usually.

Q2: If on several occasions a large amount of money was spent, then we can say "large amounts were spent".

Q3: Same as Q2. To illustrate:

1 March 2003 - 23 vehicles towed
2 March 2003 - 40 '' ''
3 March 2003 - 25 '' ''
etc.

"In April we decided to install a gate, because large numbers of vehicles had been towed in March."

However, we can also consider the March total as a whole (say 850 cars towed). Then we would say "... a large number of vehicles had been towed ...".

It is often possible to treat a group either as a single entity or as a number of constituent parts, depending on the context. For instance:

"The council made its decision." (acting as one)
"The council had their coffee after the meeting." (each member did so individually)


Cheers

John.

[MikeNewYork]

Originally Posted by maktau

Q1 : As far as I remember, 'amount of' is usually used with uncountable whilst 'number of' is used for plural. Is it correct?

Q2 : In what situation, the 'amount' should be added with 's'?
ex. Large amounts of money were spent. &
He has attracted an enormous amount of public sympathy.

Q3 : which of the following sentences is correct?
Large numbers of vehicles had been towed.
A large number of vehicles had been towed.

I should be most grateful if any persons could teach me!

You have got it right. We use "amount of" or "amounts of" before uncountable nouns. We use "number of" or "numbers of" before countable nouns. Whether or not we pluralize "number" or "amount" depends on the sense of the sentence, but there is little difference between "a large amount of money" and "large amounts of money" or "a large number of vehicles" and "large numbers of vehicles".

[MikeNewYork]

Originally Posted by John C.

Q1: Yes. Usually.

Q2: If on several occasions a large amount of money was spent, then we can say "large amounts were spent".

Q3: Same as Q2. To illustrate:

1 March 2003 - 23 vehicles towed
2 March 2003 - 40 '' ''
3 March 2003 - 25 '' ''
etc.

"In April we decided to install a gate, because large numbers of vehicles had been towed in March."

However, we can also consider the March total as a whole (say 850 cars towed). Then we would say "... a large number of vehicles had been towed ...".

It is often possible to treat a group either as a single entity or as a number of constituent parts, depending on the context. For instance:

"The council made its decision." (acting as one)
"The council had their coffee after the meeting." (each member did so individually)


Cheers

John.

I just wanted to add that your ending examples are correct in British English, but would not be normal in American English. We would be more likely to say: "The council members had their coffee...."