In the next section below is the same paragraph, except I replaced every "I" with "you", and "my" with "your". I also adjusted the verb conjugations.
For instance, "Mi llamo Juan" is changed to "Tu llamo Juan"
Be careful not to mix up tu and tú. The difference is the accent over the u. The first is the possessive "your" while the second is the pronoun "you". Refer to any verb conjugation charts if needed. I'll stick to the present tense.
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Tu llamo Juan. Tú eres de España. Tú vives con tu familia en una casa grande. Tú tienes quince años. Tu cumpleaños es el dieciocho de abril. Tú asistes a tus clases a las ocho de la mañana. Tú tomas siete clases. Tu clase favorita es la clase de inglés porque te gusta aprender otros idiomas. Tú comes con mis amigos en la cafetería todos los días. Tú hablas de tus problemas con ellos por la tarde. Tú llegas a casa a las cuatro de la tarde y termino tu tarea. Después, tú miras la televisión con tu familia.
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Original paragraph's translation to English:
My name is Juan. I am from Spain. I live with my family in a big house. I'm 15 years old. My birthday is the 18th of April. I attend my classes at 8 in the morning. I take 7 classes. My favorite class is English because I like to learn other languages. I eat with my friends in the cafeteria every day. I talk about my problems with them in the afternoon. I arrive home at 4 in the afternoon and finish my homework. Afterward, I watch TV with my family.
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What results when you replace every "I'" with "you", and replace every "my" with "yours"
Your name is Juan. You are from Spain. You live with your family in a big house. You're 15 years old. Your birthday is the 18th of April. You attend your classes at 8 in the morning. You take 7 classes. Your favorite class is English because you like to learn other languages. You eat with your friends in the cafeteria every day. You talk about your problems with them in the afternoon. You arrive home at 4 in the afternoon and finish your homework. Afterward, You watch TV with your family.