Corrigindo os erros, o texto em português fica mais ou menos assim:
São Paulo 12,de fevereiro de 2014 Queridos tio e tia, eu estou escrevendo esta carta, porque estou com muita saudade de vocês, por que me diverti muito quando eu passei as férias com vocês no sitio, foi muito bacana! Eu nadei, pesquei , andei a cavalo, foi muito legal! Quando os meus pais me ligaram para eu ir embora, fiquei muito triste. Quando voltei para casa logo que cheguei, já liguei pra vocês de saudades. Vou visitá-los em breve. Com amor, Juliana.
Passando para o inglês, fica:
Sao Paulo 12, February 2014 Dear uncle and aunt, I am writing this letter because I really missed you, why I had fun when I went on vacation with you at the site, was very cool! I swam, fished, went horseback riding, it was really cool! When my parents called me to go, I was very sad. When I returned home as soon as I arrived, I called you already homesick. I will visit them soon. Love, Juliana.
Se for traduzir o seu texto original, que postou aqui:
Sao Paulo 12, February 2014 dear uncle and aunt I am writing this letter because I have really missed you guys so much fun that when I spent the holidays with you at the site was very nice I swam, fished, went horseback riding was very cool when my parents called me to go I was very sad when I came home as soon as I arrived I called you guys already longing'll visit you soon with love Juliana