Use 'come again?' when you didn't understand or hear something properly and need it repeated.

Request Clarity

'Come again?' is a polite and informal way to ask someone to repeat themselves.

Polite Conversation

'Come again?' is casual and best used in informal settings, not formal occasions.

Use 'come again?' to show you are surprised or shocked by what someone said.

'Come again?' can imply you doubt or are skeptical about what's been told to you.

Intonation matters. Raise your pitch at the end to show that you're asking for clarification.