"The tall bear is eating the short turtle."
Translation:הדוב הגבוה אוכל את הצב הנמוך.
Hebrew grammar that simply doesn't translate to English. I think of it as a relational word. It isn't used with indefinite nouns, only specific ones. "I love את you" or "The teacher is helping את her students."
In this case, "The tall bear is eating את the short turtle."
As if there was any other kind of turtle.
"A bear eats a turtle" is not a specific relationship between two identified animals, so there is no את.
MALE TURTLE IS NOT SPECIFIED SO FEMALE TURTLE SHOULD ALSO BE CORRECT.