The past tense of contribute is contributed.
The word contribute is a verb. The past tense is contributed.
Contribute is the present simple tense.
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 past tense of "will" is "would". The past tense of "to be" is "was" or "were".
Contribute is the present simple tense.
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).
Simple past tense. Past perfect tense. Past continuous tense.
Existed is the past tense. The past perfect tense is had existed.
The past tense is schooled. The past continuous tense is 'was/were schooling'.