Spelling of verbs with -ing and -ed

Q:

When you add -ing or -ed, why don't you double the final consonant in listen, as you do in some verbs? The word ends with a single vowel and a single consonant.

Marla Yackshaw
YACKSHMS@pwcs.edu

A:

Even though the word ends with a single vowel and single consonant, the final consonant is doubled only when the stress is on the final syllable.

For example, the consonant is doubled in preferring, admitting, and occurring because the stress, in the pronunciation of the simple form of the verb, is on the second syllable (prefer, admit, occur).

In contrast, the consonant is not doubled in listening, visiting, and offering because the stress is on the first syllable (listen, visit, offer).