Hi, that's a common problem. I may refer you to a reply which I did in a previous thread that's similar to your one: First of all you should stay calm and at first you don't have to talk with a fluent speaker in a proper way. When he notices that your english level isn't that good, he'll try to use words which you can understand and even if you didn't understand a word,even a sentence,Ask friendly if he can repeat the sentence or explain you what he meant.
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