代わる

1. Origins, structure, and basic meaning

• Structure: 代わる (かわる) is an intransitive verb for one person taking another’s role or for the person in charge changing.
• Basic usage: 父に代わって店番する takes over the father’s role in watching the shop, while 担当者が代わる describes the person in charge changing.

2. Common pitfalls and similar expressions

• Person replaced and changing subject
  • In 父に代わる, に marks the person replaced, while in 担当者が代わる, が marks the role holder who changes. This is not a transitive verb for exchanging objects.