Question

quais dessas frases estão erradas
she made her dreams come true
jack is studying with his friend
mine car and hers are the same
a friend of there is coming for the weekend
your t-shirt size is bigger than hers

Answer 1

"mine car and hers are the same" - nao se usa Mine para indicar posse no inico de frase, apenas ao fim
"a friend of there" - there ( lá ou verbo haver) nao faz sentido sua utilizaçao nesta frase. portanto usasse a friend of 'me'. of 'her'. of 'his'
"your t-shirt size is bogger tham hers" - faltou o genitive form ( indica posse) entao seria o certo your "t-shirt's" ( 'S) size is bigger... para mostre que o tamanho é da t-shirt