Ago

Ago is an adverb of time used in English to indicate that an event occurred before the present moment. It requires a preceding time expression and is normally understood as referring to a point or interval in the past, rather than the future.

Typical constructions place ago after a duration or specific time: "two days ago," "three years ago," "a long time ago." It can appear in questions such as "How long ago did you move here?" or in statements like "That happened three weeks ago." The word cannot modify a noun directly and it does not appear with future references.

Usage notes include that "not long ago" emphasizes recency, while "long ago" marks a distant past. In many contexts, "ago" functions as a standard, everyday term for locating events on a past timeline relative to the present.

Etymology and history: The word is very old in English and is attested in medieval stages of the language. Its precise origin is uncertain, but it is generally treated as an ancient time-adverb related to the sense of "before now." See also time expression, temporal adverb, and history of English.