Asking to elaborate

• Why do you agree/disagree?

  Pam wyt ti'n cytuno/anghytuno?
• What's your opinion on

  Beth ydy dy farn di am
• What do you think about

  Beth wyt ti'n meddwl am
• Do you have an opinion about

  Oes barn gyda ti am
• Do you have ideas about

  Oes syniadau gyda ti am