In the case of past perfect tense, it tells us that an event happened in the past before another event in the past.
SHORT ANSWERS Yes, I had. No, I hadn’t. Yes, you had. No, you hadn’t. Yes, we/you/they had. No, we/you/they hadn’t Yes, he/she/it had. No, he/she/it hadn't. Signal words for the past perfect include already, just, once, never, not yet, until that moment,
Some of these signal words are the same as those for the present perfect, so it's important to note that words for the past perfect refer to the past.
