Y fannod (the)

• 'r is used after a vowel, e.g. Mae'r coleg, o'r ysgol.
• yr is used in front of a vowel and h when the word in front ends with a consonant, e.g.
  yn yr ysgol, cyn yr haf
• y is used in front of a consonant when the word in front ends with a consonant, e.g. yn y dref, cyn y gaeaf