The treiglad meddal or soft mutation is a change in the first letter of a word. It affects words starting with one of nine letters. The treiglad meddal is the most common one, and you'll come across it all the time. It happens for all sorts of different reasons, but we'll use one to practise with - after 'o', which means 'from'.

• Pontypridd - o Bontypridd
  


• Talybont - o Dalybont
  


• Caernarfon - O Gaernarfon
  


• Bangor - o Fangor



• Dolgellau - o Ddolgellau



• Gwent - o Went



• Llanelli - O Lanelli



• Machynlleth - O Fachynlleth



• Rhydaman - O Rydaman