Quantifiers are words that express quantity and modify nouns. Some common quantifiers for countable nouns include: too many, many, a few, few, several, none of. For uncountable nouns: too much, not much, a little, little, a bit of, a good deal of. Quantifiers can also express an entire amount: all of, some, most of, not enough, enough, a lot of, lots of, plenty of, a lack of. Examples are provided to illustrate the usage of quantifiers with both countable and uncountable nouns.