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