Questions & Answers about La roko kuŝas apud ŝtono.
Why is there la before roko but not before ŝtono?
La is Esperanto’s definite article, the same for all nouns, and it works like English the.
So la roko means the rock: a specific rock.
But ŝtono without la is indefinite, so it means a stone or just stone, depending on context. Esperanto normally does not have a separate word for English a/an.
Could I also say La roko kuŝas apud la ŝtono?
Yes. That would mean the rock is lying beside the stone.
Use la ŝtono if the stone is also specific and known to the speaker and listener. Use just ŝtono if it is not specific, or if the sentence simply introduces it as a stone.
So the choice depends on context, not on grammar.
What does the -as in kuŝas mean?