They are/were great experiences

My friend, Jack, and I have known each other for two years. We have many common interests. We go mountain climbing together. So far, we have climbed Mt. Jade and Mt. Ali together. They ___ great experiences.

Which word should I use to fill in the above blank, are or were?

Hi Sitifan

I’d use “were” in that particular context. In other words, “they” would refer to the two specifically mentioned mountain climbs which took place in the past – two past events.
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