Choosing between Present perfect and Past perfect

Question

The task is about choosing the past perfect/present perfect/past simple. And I am asking about the part with ‘change’:

5. Last week, I (run) __ into an ex-girlfriend of mine. We (see, not) __ each other in years, and both of us (change) __ a great deal. I (enjoy) __ talking to her so much that I (ask) __ her out on a date. We are getting together tonight for dinner.

Should I use ‘had changed’ or ‘have changed’? It is confusing me, because by the definition of past perfect - Action is finished, and it is followed in the story. But by the definition of present perfect - Action has finished in past and has an impact today (persons have changed) and it continues (ageing is not stoppable process). I would like more to hear, how to choose the correct tense in those complicated situations, rather than just - ‘Yea, that's the correct answer’. P.S. For other brackets I used - ‘run’, ‘didn't see’, ‘Question’, ‘had enjoyed’, and ‘asked’. I hope that I am not failing too hard :D Thanks ;)

Answer 1

You ran into your her last week, but this meeting has resulted in a date tonight. The effect extends into the present, so I would choose present perfect: "we have both changed a great deal" ( the change started in the past and has an effect now: we like each other again.)

However, I would choose past perfect for "we hadn't seen each other in years", because meeting each other again happened last week = past and "not having seen each other" took place in the years before last week = past before the past.

Because you enjoyed the meeting that took place last week you asked her out last week, this is past time, so use past simple.

Answer 2

The blanks are "changed", "enjoyed", and "asked". It's because most verbs have past tenses that end with "-ed". If the event is happening in the past you can tell by the way they use verbs. Also there are some verbs, irregular verbs, that don't have past tenses, like the word "put". You wouldn't say "I putted my shirt on." You would still say "I put my shirt on." Unlike how with regular verbs, like "change", you'd say "I changed my pants" instead of "I change my pants." If you do slip up, people will still understand you.