so which is it? Why are they different and how to I figure out which one to place in the sentence? Is it a male-female difference?
right: gatas is female, gatos is male. In the multiple choice questions you can select 2 answers.
In spanish the gender is important, of course. In this case:
Gato/Gatos (male cat/cats)
Gata/Gatas (female cat/cats)
The only difference in use gata/gato in a sentence is what you want to mean, keeping in mind the gender.
My neighbor had a cute cat named Mary / Mi vecino tenia una linda gata llamada Mary
(Mary is a female name, then you must use gata and not gato)
- Does your child wish a cat ? / ¿Tu hijo quiere un gato/gata?
(In this case you can use both, but it is common using gato, when the gender is not especified in the sentence)
I hope this helps you with your doubt and not confuses you more...