use of particles on direct object

Question

When is the use of correct particle (を or が) on the direct object of a transitive verb, for example:

• shigoto o owarimasu
• shigoto ga owarimasu

What is the exact meaning in each other, please.

Answer 1

Many Japanese verbs have transitive and intransitive versions. Basically, 終わる (owaru) is an intransitive verb. 終える (oeru) is the transitive equivalent. So here are the most basic usages:

• 仕事が終わります。 Shigoto ga owarimasu. (intransitive)
  The task finishes.
• 仕事を終えます。 Shigoto o oemasu. (transitive)
  I finish the task.

In plain and active sentences like your example, the direct object of a transitive verb is always marked with を. In potential and passive sentences there are a lot more to know.

• Potential: The difference between が and を with the potential form of a verb.
• Passive: Passive form - The exact difference between を and が

So, these are the generic rules.

But in case you have seen ～を終わる before, please read on.

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However, 終わる (owaru) happens to have an exceptional transitive usage, too. See: When is 終わる used as a transitive verb? It's the fourth definition of this dictionary entry.

• 今日の授業を終わります。
  That's all for today's class.

Exceptional transitive usages are seen in limited contexts in some intransitive verbs. I think this transitive usage of 終わる is limited to "That's it/all (for today)" as a closing word of a lesson/meeting/etc. In such contexts 今日の授業が終わります sounds highly unnatural (it sounds the class closes on its own). For other meanings, you have to use ～が終わる or ～を終える following the general rule above. For example, you cannot say 食事を終わる nor 宿題を終わる. If you want to say "Let's have a party when you have finished with the novel":

• その小説が終わったら、パーティーを開きましょう。: OK
• その小説を終えたら、パーティーを開きましょう。: OK
• [×] その小説を終わったら、パーティーを開きましょう。: ungrammatical

There is another exception regarding 終わる; when this is used as an auxiliary verb (i.e., when it follows a stem of another verb and forms a compound verb that means "finish ～ing"), verb + 終わる works as a both transitive-and-intransitive verb. In this case, を and が are interchangeable.

• その小説を書き終わったら、パーティーを開きましょう。: OK
• その小説が書き終わったら、パーティーを開きましょう。: OK
• その小説を書き終えたら、パーティーを開きましょう。: OK

See also:

• In what contexts can "始{はじ}める" be an intransitive verb?