na and u + accusative in set phrases of manner and result

You already know na and u with the accusative for movement (idem na posao, ulazim u kuću) and in the time phrase na vreme. This lesson adds two uses where nothing moves anywhere at all. na + accusative builds fixed phrases that say how something is done, and u + accusative names what something becomes — the colour, shape or state it ends up in. In both, the accusative is simply part of the phrase, just as it is in na vreme.

na + accusative: HOW something is done

These phrases are learned as whole pieces. Each one works like an adverb: it tells you the manner, not the place.

The noun is in the accusative singular, and an adjective in front of it agrees: prvi pogled (masculine, looks like the nominative), moju sreću, našu sreću, svoju ruku (feminine, -u).

• Zaljubili su se na prvi pogled. — They fell in love at first sight.
• Doručkovao sam na brzinu. — I had breakfast in a hurry.
• Otvorili su vrata na silu. — They opened the door by force.
• Na moju sreću, autobus je kasnio. — Luckily for me, the bus was late.

na glas is very often written as one word, naglas (Čitaj naglas! — Read out loud!). Both mean the same thing. And do not confuse these with na + locative: na miru (in peace) is a locative phrase you only need to recognise.

u + accusative: what something BECOMES

After verbs of changing — ofarbati / obojiti (paint, dye), pretvoriti (se) (turn into), iseći (cut up), obući se (dress) — u + accusative names the result. English often has no preposition at all here (paint it yellow), but Serbian always needs u.

Colours take one fixed form: the neuter accusative singular, which ends in -o — whatever the painted thing is. Think of it as "into the yellow". So after u, a colour always takes the neuter form in -o, whatever is painted.

Other results are ordinary nouns in the accusative singular, with any adjective agreeing exactly as it would with a direct object:

A person or animal after u keeps the animate accusative you know from direct objects: u drugog čoveka, u pravog gospodina (-og, not -i).

The passive participle you already know keeps the same phrase: obojen u žuto (painted yellow), pretvoren u muzej (turned into a museum).

Cutting: u kockice or na komade

With iseći (cut up) both prepositions appear, and both take the accusative (here plural): u kockice (into cubes), na komade (into pieces), na kriške (into slices). The shape is part of the phrase — learn u kockice and na komade as they are.

• Iseci luk na komade, a paprike u kockice. — Cut the onion into pieces and the peppers into cubes.

Two traps. First, never make the colour agree with the thing: it is ofarbati ogradu u plavo, not u plavu. Second, u + accusative is the CHANGE, u + locative is the STATE: Obukla se u crno (she dressed in black — acc) but Bila je u crnom (she was in black — loc).