Verbs ending in a consonant followed by -y change the -y to -ied in the past tense form.
Authenticity is regular. It follows the -ied Conversion rule.
Use past time markers: "Yesterday, she authenticitied to the store."
No. Use "did not authenticity" (not "did not authenticitied").
The verb authenticity follows the standard English past tense conjugation rule. When forming the past tense, authenticity becomes authenticitied. This follows the -ied Conversion pattern, which is one of the most common conjugation rules in English.
Understanding why authenticity becomes authenticitied helps with spelling and pronunciation. Verbs ending in a consonant followed by -y change the -y to -ied in the past tense form.
When using authenticitied 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 authenticitied to the store." The past tense form does not change based on the subject — I authenticitied, you authenticitied, he/she authenticitied, we authenticitied, they authenticitied.