• Basic forms
• 換える — change; replace / base form
• 換えます — changes; replaces / masu form
• 換えた — changed; replaced / ta form
• 換えて — changing … / te form
• 換えない — do not change / negative
• 換えれば — if (one) changes / conditional
• Common expressions
• 服を換える — change clothes
• 席を換える — change seats
• 考え方を換える — change one’s way of thinking
• More
• 換えている — is changing / state

換える（かえる） is an ichidan transitive verb. It means to exchange one thing for another of the same kind, focusing on replacement through substitution. 換える emphasizes exchanging items (money, tickets, shifts, roles), while 替える refers to replacing something with a substitute, and 変える refers to changing a state, condition, or quality.

• Basic forms
• 換わる — be changed; be replaced / base form
• 換わります — is changed / masu form
• 換わった — was changed / ta form
• 換わって — changing … / te form
• 換わらない — does not change / negative
• 換われば — if (something) changes / conditional
• Common expressions
• 時代が換わる — times change
• 担当者が換わる — the person in charge changes
• 雰囲気が換わる — the atmosphere changes
• More
• 換わっている — has changed / state

換わる（かわる） is a godan intransitive verb. It describes a change that occurs as a result of an exchange, without focusing on who caused it. It often refers to roles, duties, shifts, or positions being exchanged.