~た
RuleVerb ta-form: the plain past/perfective, matching the polite -mashita.
Curiosity
You have learned "tabemashita." So how do you make the plain past "ate" you would say to a friend?
Intuition
If you can build the te-form, the ta-form is free: just swap te for ta. The sound-change rules are exactly the same.
Visualization
taberu (dictionary) → tabeta (ta-form). Tap each step to follow the change.
食べるdictionary form
Essence
Ichidan: drop ~ru, add ~ta (taberu → tabeta). Godan use sound-change: kaku → kaita, oyogu → oyoida, nomu → nonda, matsu → matta, hanasu → hanashita. Irregular: suru → shita, kuru → kita, iku → itta.
Examples
昨日、寿司を食べた。
I ate sushi yesterday.
先週、京都へ行った。
I went to Kyoto last week.
もう宿題をした。
I already did my homework.
Mini-quiz
What is the ta-form of "kaku" (to write)?