Verbs ending in -e simply add -d to form the past tense. This is the most straightforward regular rule.
Trephine is regular. It follows the -d Addition rule.
Use past time markers: "Yesterday, she trephined to the store."
No. Use "did not trephine" (not "did not trephined").
The verb trephine follows the standard English past tense conjugation rule. When forming the past tense, trephine becomes trephined. This follows the -d Addition pattern, which is one of the most common conjugation rules in English.
Understanding why trephine becomes trephined helps with spelling and pronunciation. Verbs ending in -e simply add -d to form the past tense. This is the most straightforward regular rule.
When using trephined 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 trephined to the store." The past tense form does not change based on the subject — I trephined, you trephined, he/she trephined, we trephined, they trephined.