参る

1. Origins, structure, and basic meaning

• Structure: 参る(まいる) is a humble equivalent of 行く or 来る; in another use it means being overwhelmed, troubled, or exhausted.
• Basic usage: For humble movement it appears as in 明日参ります; for an unbearable situation it appears as in 暑さには参った.

2. Common pitfalls and similar expressions

• Separate the two senses by context
  • With a destination or time it is likely humble movement, while 〜には参った means that something has overwhelmed or defeated the speaker.
• Difference from 行く and 来る
  • 行く and 来る are neutral movement verbs, while movement-related 参る humbly lowers the speaker or the speaker's side.