"कुत्ता बिल्ली के ऊपर चलता है।"
अनुवाद:The dog walks over the cat.
Yes, you can take it like this : In English, articles are always needed for singular nouns.
So you cannot say "Elephant is huge". Though, when you say "The elephant is huge", it shows that you're speaking of a specific elephant. If you want to generalise this statement, saying that all elephants are huge, you can say "An elephant is huge" or better, "Elephants are huge". So, for plural nouns, you can do without the article "the", but that generally generalises the statement.