"There is" or "There are" a large quantity of people? [duplicate]
I thought this excerpt from Oxford Dictionaries was instructive:
Although the expression ‘a number’ is strictly singular, the phrase ‘a number of’' is used with plural nouns (as what grammarians call a determiner (or determiner)). The verb should therefore be plural:
A number of people are waiting for the bus.
This is not the case with ‘the number’, which is still singular:
The number of people here has increased since this morning.
I'd use number instead of quantity here. I'm not a native speaker, but
There is a large number of people
sounds more natural.