Hi Anastasia, There could be a few possible reasons for this. 1.It could be that the native speaker is saying 'high', which has the same pronunciation but different meaning. 2. 'Hi' could also be used for grabbing someone's attention, maybe if they think that person isn't listening. 3. They could be saying 'Hi' to someone they see passing whilst halfway through saying a sentence. These are all possible reasons, but the real reason would depend on the context. I hope that helps!

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