While irregular verbs are often a focus of grammatical errors, regular verbs are a frequent source of spelling errors.
Most regular verbs form their past tense by adding -ed to the base: accept/accepted.
A few verbs form the past tense with a -t ending: build/built.
Some spelling errors result from the fact that the -ed ending may be pronounced in one of three ways:
A common spelling error occurs with words that end with the sound /t/, but are spelled with –ed. For example, wrecked, might be misspelled as “wreckt.”
Some of verbs that end with the sound /t/ do spell the sound with -t.
Some verbs that end with the /t/ sound may be spelled with either -ed or -t. The -t ending for these verbs is more common in British spelling.
Most American speakers would probably consider leapt, leant, learnt, smelt, and spelt out-and-out misspellings. Burnt, dreamt, knelt, spilt, and spoilt, however, do occur in U.S. speech and writing.