Questions & Answers about Ptice lete nad brdom.
Why does nad take the instrumental case brdom here if the birds are moving?
We use the instrumental case with nad (above) to show where an action is taking place. Even though the birds are flying, their flight happens entirely in the space above the hill. If the sentence described movement towards a new destination, we would use the accusative case instead.
How is nad different from the preposition na?
The preposition na usually means "on" and implies physical contact with a surface. The preposition nad means "above" or "over" and implies there is empty space between the objects. Since the birds are in the air, we use nad.
What is the base form of brdom?
The base form is brdo (hill), which is a neuter noun. Because the preposition nad requires the instrumental case for a stationary location, we replace the -o with the neuter instrumental ending -om to make brdom.
The verb is lete (they fly). What is the infinitive?
The infinitive is letjeti (to fly). It belongs to a group of verbs that use the -e ending for the "they" form in the present tense, rather than the more common -u or -aju endings.