"The candles are on the cake."

Translation: Lumânările sunt pe tort.

[xavi75724]

Nouns after prepositions are without articles unless they are with an adjective

Lumânările sunt pe tort.

Lumânările sunt pe tortul meu.

Lumânările sunt pe tortul fără zahăr.

[EricGoodem]

Why isn't it tortul instead of tort?

[VHAZVLL]

Probably when you use 'pe tort' is not necesary to use the article. because there are examples when we use 'pe masă' and it does not have the article. I speak spanish (similar language to romanian almost on everything) and have understood that the word 'pe' includes the article.

[Soyjack1488]

So it seems the general rule is when a noun is preceded by locative prepositions, article is not needed.