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"Hi" is a form of "hi", an interjection which is often translated as "hola". "I'm" is a contraction which is often translated as "soy". Learn more about the difference between "I'm" and "hi" below.
I'm(
aym
)A contraction is a shortened form of a word or group of words made by omitting a sound or letter (e.g. don't).
hi(
hay
)An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g. Wow!).
1. (colloquial) (salutation)
A word or phrase that is commonly used in conversational speech (e.g., skinny, grandma).