I wrote "He loves the animals" and was marked correct, but "He loves animals" would have also been correct. I thought "He loves animals" (a general love of animals) would be "ele ama de animais", DE instead of OS, is that right or wrong?
The, you just need to leave OS out: ele ama animais. Use DE after gostar, but not after amar.
Any rule why we use DE after gostar but not amar? They are both regular verbs right?
No rules. They are both regular but some verbs require specific prepositions.
I was marked wrong for putting "Ele ama animais" I missed of "os", why do you need the "os"?
"Ele ama animais" is correct too... but is more generic, as if you are talking about all animals of the world.
Is " He loves his animals" correct ? Could "os" be a pronon in this case ?
he loves his animals = ele ama seus animais
ele ama os animais = he loves the animals
"os", "as", "o" and "a" are always articles.
os and as = plural o and a = singular