Countless times, I have confused non-native English speaking friends with my habit of saying "I'm down". They often understand this in a negative context, as if I'm saying that I am not happy about something.
When American English speakers tell you, "I'm down", they're not referring to their emotion, but rather their interest. They expressing that they WANT to participate in whatever you may be doing.
Listen in closely, and practice along with me as we get a well-rounded view of the common American idiomatic expression, "I'm down"!
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