Answer:
Cuando yo voy al zoológico, yo veo muchos animales. Mis favoritos son los monos, son muy graciosos y peludos. Los elefantes son enormes, mucho más grande de lo que me imaginaba. Las jirafas son muy altas y hermosas. Pude ver también muchos loros, ¡muy coloridos! El tigre es como un gato gigante, me dio un poco de miedo a decir verdad.
Explanation:
In the first sentence the "yo" is redundant. It would be much better to say "Cuando voy al zoológico, veo muchos animales". This is because the verb "voy" can only refer to myself so there's no need to use the "yo". It different in English when you always need the subject. This is the text in English:
When I go to the zoo, I see a lot of animals. My favorites are the monkeys, they're really funny and hairy. The elephants are huge, much bigger than I imagined. The giraffes are very tall and beautiful. I could also see lots of parrots, so colorful! The tiger is like a giant cat, I was a little scared of it to tell you the truth.