Cook is the present tense.
Present Perfect - Have/Has cooked. Past Perfect - Had cooked. Future Perfect - Will have cooked.
Let's look at the verb 'sing'. Past tense - sang Past participle - sung Present tense - sing/sings Present participle - singing Future tense - will sing
I/He/She/It was cookingWe/You/They were cooking
The past tense is cooked.
The verb is is the present tense.
"After" can be used with both present and past tenses. For example, "After I arrived home, I cooked dinner."
The past tense of did is did. The present tense of did is do. The future tense of did is will do.
It was, (past tense) it is, (present tense) it will be( future tense)
Past tense I had Present tense I have Future Tense I will have
Past perfect tense.
"Has" is in present tense. The past tense is "had".
No 'is' is present tense. am/is/are = present tense was/were = past tense