No it is incorrect. Past tense of purchase is purchased. Past tense for do is did.
Have done is correct. When using have as an auxiliary verb, it's paired with a past participle.
Yes, when using the past perfect tense.
"What I did is" is correct. It does not matter that the doing occurred in the past: it is still what I did, and will always be what I did. The answer below represents a very popular misuse of tenses. You are talking about something you did in the past, because you are using "did", therefore the correct statement is, "What I did was..." If you were to use the verb "is" or "to be" then that means you are speaking about the present, so the correct statement using this verb is "What I am doing is..."
what is the past participle of correct
The correct grammar is "had departed." This is because "departed" is the past participle form of the verb "depart," and when using the past perfect tense, we need to use the auxiliary verb "had" followed by the past participle form.
The past tense and past participle of correct are both corrected.
The past tense of correct is corrected.
The correct past tense is "have shrunk." "Shrunk" is the correct past participle form of the verb "shrink."
The past participle of "correct" is "corrected."
The past tense is put.
No, growed is incorrect.The correct simple past tense of grow is grew. The past participle is grown.
The correct spelling is "purchase" (buying something).