Answer:
Think about it like male and female articles.
Explanation:
If the word ends in a then the answer will be "la". That's the female article. If the word ends in o then the answer will be "el". That's the male article. "Los" is also a male article and "las" is also a female article. Those are the basics of Spanish articles.
Answer:
It's incorrect
Explanation:
It should be "Corre rapidamente"
By adding that "s" at the end you are making it a statement ("you run very fast") instead of a command
Voy a la playa despues de la escuela los martes y viernes.