This verb follows the standard English past tense rule: simply add -ed to the base form.
Fail is regular. It follows the Standard -ed rule.
Use past time markers: "Yesterday, she failed to the store."
No. Use "did not fail" (not "did not failed").
The verb fail follows the standard English past tense conjugation rule. When forming the past tense, fail becomes failed. This follows the Standard -ed pattern, which is one of the most common conjugation rules in English.
Understanding why fail becomes failed helps with spelling and pronunciation. This verb follows the standard English past tense rule: simply add -ed to the base form.
When using failed in writing, remember that it functions as a past tense verb and typically appears with time markers like yesterday, last week, or ago. For example: "Yesterday, she failed to the store." The past tense form does not change based on the subject — I failed, you failed, he/she failed, we failed, they failed.