No, because the Greek says τους which refers to specific elephants not elephants in general.
No, because the singular is not ελέφαντος (second declension in -ος) but ελέφαντας (first declension in -ας).
(Well, historically, third declension: ελέφας. But third-declension nouns mostly got put into the first declension in Modern Greek.)
"first, second, third declension" refers to groups of nouns that inflect similarly.
For example, first-declension nouns end in one of -α -η -ας -ης, while second-declension nouns end in one of -ος -ο.
All second-declension nouns have a genitive in -ου, for example, while first-declension nouns do not -- they have -ας -ης (feminine) or -α -η (masculine) instead.
Thank you! Do you mean first declension (singular) is "I..." ( declined Verb), second is" you ...."( declined Verb), third he,she, it... (declined Verb) Plural: we, you, they....like in german or roman languages ?? every verb has its own ending in every case ? I´m sorry. The time, when I was in school is more than forty years ago...