How to say "Be" in Japanese

When translating "be" into Japanese, you must choose carefully between 治る and 役立つ. In Japanese, 治る (なおる (naoru)) is typically associated with "to be cured, to get well (intransitive) / to be repaired, to be fixed (intransitive)" (Syllabus Level: N4) and represents Used for illnesses getting better. On the other hand, 役立つ (やくだつ (yakudatsu)) maps to "to be useful, to be helpful" (Syllabus Level: N3) and represents An intransitive verb. Used to describe something that serves a purpose or provides assistance. Often followed by に.. A literal translation of "be" can often sound unnatural to native Japanese speakers if mixed up!