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