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What is the difference between:
And similarly, if I want to say "recently I went to my favourite cinema and found it's closed down" would I say 我最近去了我最喜欢的电影院，可是发现了它已经关闭了? Or should the first and second 了s be omitted? I know that this 了 means "action completed" but I've seen many example sentences where actions are completed yet there is no 了, which has left me confused about when I should include it.