The first person singular pronoun "I" usually refers to yourself (or the speaker). In the plural form it is "we."
I really am passionate about this.
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Well, we are very excited to have you with us!
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The second person pronoun "you" can be singular or plural and usually refers to the person or persons you are addressing.
What will you have for lunch?
Caption 23, Caralie and Annie - Get to know each otherPlay Caption
The third person pronoun refers to someone other than the person you are speaking to, and is "he" (male) or "she" (female) or "it" (object) in singular, "they" in plural:
She is elegant and we wish her luck this weekend.
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They thought it was a hoax.
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Read the personal pronoun article in English and in your native language to help you understand the basics. Write a simple sentence in your native language for each of the personal pronouns, then translate them to English. Search for some personal pronouns on Yabla English and see some different examples of how they are used in context.