I am teaching English in Brazil and I am having a hard time explaining when to use "in the" and "at the" (prepositions)
In general "at the" refers to a general location.
We had lunch at the beach.
I met him at the theater.
We had drinks at the bar.
I general, "in the" refers to being inside of or surrounded by something.
We had lunch in the park.
John was sitting in his room.
He saw his reflection in the mirror.
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