The suffix -er typically forms nouns that denote a person or thing that performs a specified action or has a particular quality. It can also indicate comparative degree or indicate someone's profession or occupation. For example, a teacher is someone who teaches, a singer is someone who sings, and a writer is someone who writes. In terms of comparative degree, it can transform an adjective into a comparative form, such as taller (more tall), faster (more fast), or stronger (more strong).
