How to form the past simple?
1. Add an -ed to the end of the verb or just 'd' if the vowel already ends in an 'e'.
play -> played look -> looked climb -> climbed explore -> explored
2. Y Rule: y turns to i, except if the 'y' comes after a vowel (a,e,i,o,u)
carry -> carried hurry -> hurried BUT play -> played
3. Double Rule: Consonant is doubled if it is right before a vowel.
stop -> stopped dot -> dotted hop -> hopped