in と at と in the park と at the sport center と at the cinema はどう違いますか？説明が難しい場合は、例文を教えて下さい。

@sealexe:
What the dictionary officially says:
at: In or near the area occupied by in or near the location of
in: Within the limits, bounds, or area of

What it really means: using "in" to note a general location and "at" for a more specific location.

Examples for in, "I'm in the United States" or "I'm in my backyard"
Or for at
"I'm at the sport center across the street." Or "I'm at my aunts place."

So in is generally used for a larger area where there are numerous specific locations possible. At is used for a specific location or thing.

I hope this helped! :)