Breakdown of im Kaffee
der Kaffee
the coffee
So you see that our coffee is masculine. There are very few, close to no rules about which is what gender, just try to learn them with memos like German coffee is for tough guys
im
in the masculine, neuter
in dem is almost always contracted to im
The only exception is when you point at a place and insist 'inside this one, not in the other one'
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