In Engpsh, you can say "I have eaten dinner" or "I ate dinner". The past tense of "eat" is "ate", so you would use the past tense to indicate that you have already eaten dinner. The sentence "I have eaten dinner" is written in the present perfect tense, which is used to describe an action that was completed in the past but has a present effect.

To read this sentence aloud, you would pronounce the verb "eaten" as "ee-tn" and the verb "ate" as "eyt". The past participle "eaten" is pronounced with a long "e" sound, while the past tense verb "ate" is pronounced with a short "a" sound.