'Operation' is a noun not a verb, so it cannot have a past tense. A verb related to 'operation' might be operated, in which case the past tense would be be the same: operated. You could convey past tense though by adding did opreate, or had operated, but these are complex past tenses (with two verb forms).
Flew is the past tense of fly; counted is the past tense of count.
The past tense is stepped.
The past tense is enumerated.
The past tense is rectified.
The past tense of increase is increased.
"Operation" is a noun and so doesn't have a past tense. Only verbs have past tenses.
the past tense of am is was and the past tense of has is had
The past tense of get is got. For isn't a verb and so doesn't have a past tense. The past tense of has is had. Had is already the past tense. The past tense of have is had.
Was and were are both the past tense of be. The present tense is: I am he is you are they are The past tense is: I was he was you were they were
The correct spelling (past tense of the verb to operate) is operated.
The past tense of "will" is "would". The past tense of "to be" is "was" or "were".
Wrote is past tense. It is the past tense of write.Wrote is already a past tense.
The past tense of "finish" is "finished". The past tense of "be" is "was" (singular) or "were" (plural).
The past tense is schooled. The past continuous tense is 'was/were schooling'.
The three kinds of past tense are simple past, past continuous, and past perfect. Simple past is used to describe a completed action at a specific time, past continuous describes an action that was ongoing in the past, and past perfect is used to show that one action in the past happened before another.
Existed is the past tense. The past perfect tense is had existed.
The past tense of "meet" is "met." For example: "I met my friend for lunch yesterday."