Quantifiers show amount: much, many, a few, a little, some, any, several. Use 'many' with countable nouns and 'much' with uncountable. Adverbs compare using more/most or -er/-est: fast, faster, fastest; carefully, more carefully, most carefully. Relative pronouns (who, whom, whose, which, that) join clauses; interrogative pronouns (who, what, which) ask questions.