The words were and was are both past tense of be.
"Had" is past tense.
The word nice is an adjective and so doesn't have any tenses. It is only verbs that have tenses.
Say Past tense - said. Present tense - say/says/saying. Future tense - will say. Get Past tense - got. Present tense - get/gets/getting. Future tense - will get.
Past: tried. Future: will try. going to try Present: I try, he tries.