* Noun: When referring to two people or things together (e.g., "A young couple was dancing.")
* Verb: When meaning to join or connect two things (e.g., "The carpenter coupled the two pieces of wood.")
* Adjective: When meaning "two" or "a pair" (e.g., "They bought a couple of bottles of wine.")
To determine the part of speech, look at how the word is used in the sentence.