The Prefix ξανα- (“again / re-”)
Greek builds “do something AGAIN” with a single, highly PRODUCTIVE prefix - ξανα-, glued to the front of almost any verb: γράφω (“I write”) → ξαναγράφω (“I rewrite / write again”), βλέπω (“I see”) → ξαναβλέπω (“I see again”), διαβάζω (“I read”) → ξαναδιαβάζω (“I re-read”), τρώω (“I eat”) → ξανατρώω (“I eat again”). It is the exact counterpart of English “re-” + “again”, and it attaches FREELY - you can coin ξανα- on a verb you have never met the compound of, and be understood. The verb underneath keeps its ordinary conjugation, so ξανα- rides on top of every tense: present ξαναγράφω, future θα ξαναγράψω, past ξαναέγραψα / ξανάγραψα. Stress stays on the base verb’s own syllable (ξαναγράφω, like γράφω); ξανα- is an unstressed prefix. Because it is so productive, ξανα- is the first tool of word formation: knowing one verb hands you its “again” version for free.
The rule
The prefix ξανα- means “again / re-” and is the freest tool of Greek word formation. Glue it to the front of almost any verb and you get that verb’s “do-it-again” version: γράφω → ξαναγράφω (“rewrite”), βλέπω → ξαναβλέπω (“see again”), διαβάζω → ξαναδιαβάζω (“re-read”). It is productive - it attaches freely, so you can coin ξανα- on a verb you have never met the compound of (τρώω → ξανατρώω) and be understood. The base verb keeps its ordinary conjugation, so ξανα- rides on every tense: present ξαναγράφω, future θα ξαναγράψω. And it is unstressed - the accent stays on the base verb’s own syllable (ξαναγράφω, like γράφω). Read a ξανα- word by peeling off the prefix and adding “again” to what remains.