1. The word ends in a single consonant.
* AND
* the consonant is preceded by a single vowel.
* AND
* the word is stressed on the last syllable.
Examples:
* Stop -> Stopped (stress is on the last syllable, "stop")
* Clap -> Clapped (stress is on the last syllable, "clap")
* Plan -> Planned (stress is on the last syllable, "plan")
Exceptions:
* Words ending in "w" or "x" do not double the final consonant.
* Saw -> Sawed
* Fix -> Fixed
* Words ending in "y" preceded by a consonant change the "y" to "i" before adding "-ed".
* Try -> Tried
* Cry -> Cried
2. The word ends in a consonant, but the stress is not on the last syllable:
* Open -> Opened (stress is on the first syllable, "o")
* Offer -> Offered (stress is on the first syllable, "of")
Key Points to Remember:
* Double the consonant only if ALL three conditions are met (single consonant, single vowel before it, stress on the last syllable).
* This rule applies to the past tense and past participle forms of verbs.
* Not all words follow this rule. Check a dictionary or grammar guide if you are unsure.