Breakdown of Il lago di montagna è profondo.
essere
to be
la montagna
the mountain
di
of, from
il lago
the lake
Questions & Answers about Il lago di montagna è profondo.
Why is it lago di montagna instead of just montagna lago like in English?
Why do we use di here instead of della?
We use the simple preposition di without a definite article when we are describing the general type or category of something. Lago di montagna describes what kind of lake it is. If you said il lago della montagna, it would specifically mean the lake belonging to one specific mountain.
Does the adjective profondo agree with lago or montagna?
It agrees with lago (lake), which is the main subject of the sentence. Since lago is a masculine singular noun, profondo takes the masculine singular ending -o. Even though montagna is feminine, it is just part of the description. If we were describing a valley (valle, which is feminine), it would be la valle di montagna è profonda.