To be useful or helpful; to serve a purpose or provide practical benefit.
この辞書は日本語の勉強にとても役立つ。
This dictionary is very useful for studying Japanese.
経験があれば、新しい仕事でもきっと役立つだろう。
If you have experience, it will surely be useful in a new job.
メモを取る習慣は後で思い出すときに役立つ。
The habit of taking notes is helpful when you need to recall things later.