Answer:
1. Cierto
2. Falso
3. Falso
4. Cierto
5. Falso
6. Cierto
I don't get 7 and 8, sorry.
Explanation:
A and C are grammatically correct.
Translation of A: We see a snake.
Translation of C: We see Sergio.
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B and D are missing a small word.
Correction of B: Nosotros vemos *A* Tomas.
Correction of D: Nosotros vemos *A* Jorge.
They are both missing the word "a."