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