In English, many verbs can be used both intransitively and transitively with no change in form.
For example, end works in both:
The class ends.
I end the class.
In Japanese, however, we often have two similar, but separate verbs:
授業が終わる。 (Jugyō ga owaru.) = The class ends. (intransitive)
私が授業を終える。 (Watashi ga jugyō o oeru.) = I end the class. (transitive)
we can loosely group these pairs into five categories. This can be a useful reference, but don’t worry too much about memorizing every pattern. The most effective way is to see and use these verbs often, until they feel natural.
Keep in mind that the left-side verb is intransitive (自動詞 Jidoshi) and the right-side verb is transitive (他動詞 Tadoshi).
Pattern 1: Transitive verbs end in -eru
Pattern 2: Intransitive verbs end in -eru
Pattern 3: Intransitive ends in -ru, transitive ends in -su
Pattern 4: Intransitive ends in -iru, transitive ends in -osu
Pattern 5: Other exceptions
Final Thoughts
Japanese transitive and intransitive verb pairs can be confusing. There are patterns, but also many exceptions. English often uses just one verb, while Japanese makes a distinction.
Don’t worry if you can’t memorize them all at once. The best way to learn is to see these verbs in real sentences, notice the patterns, and gradually get used to them.
Patterns help you get started, but real fluency comes from exposure and practice.