The document discusses the three different pronunciations of the "-ed" ending in regular past tense and past participle verbs in English. It can be pronounced as /t/ if the base verb ends in /t/, /d/ or /ɪd/ if the base verb ends in /d/ or a voiced sound, or /ɪd/ if the base verb ends in an unvoiced consonant. It provides examples of verbs that follow each rule and an exercise for the reader to practice identifying the pronunciation of "-ed" in different verbs.