The present verbal adverb

Two things at once, one person doing both

English can squeeze a second action into an -ing phrase: "I read a book waiting for the train", "Coming back home, I met an old friend." Serbian has a form that does exactly this job: čekajući (waiting), vraćajući se (coming back). It packs a whole clause (while I was waiting) into one word plus whatever belongs to it.

This form never changes. It is the same for a man and a woman, for one person or many, in a past, present or future sentence. The main verb carries the person and the tense; the -ći form only says "at the same time". Grammar books call it the present verbal adverb (glagolski prilog sadašnji).

How to build it: the oni-form plus -ći

Take the present tense form for oni (they), which you already know for every verb, and add -ći. Nothing else is needed, so the three verb classes give three endings you can recognise at once.

• a-verbs end in -ajući: čitajući, čekajući, gledajući
• i-verbs end in -eći (their oni-form ends in -e): govoreći, noseći, tražeći
• e-verbs end in -ući (their oni-form ends in -u): pišući, pijući, putujući

Always start from the oni-form, not the infinitive. pisati gives pišući, because the oni-form is pišu; putovati gives putujući, because the oni-form is putuju.

Reflexive verbs keep se

A verb that has se keeps it in this form too: vraćati se → vraćajući se, voziti se → vozeći se, spremati se → spremajući se. Dropping se changes the meaning (vozeći is "driving" something, vozeći se is "riding" in it).

Only from imperfective verbs

The form describes an action that is in progress while something else happens, so it is made only from imperfective verbs: čitati → čitajući, pisati → pišući. A perfective verb such as pročitati or napisati has no -ći form at all. (Completed actions get a different form in the next lesson.)

Same time

The -ći action happens at the same time as the main verb, whatever that verb's tense is: Čitam knjigu čekajući voz (now), Pisala je pisma putujući vozom (in the past). It can stand before or after the main clause; in front, it is followed by a comma.

The one strict rule: the same person does both

The person doing the -ći action must be the subject of the main verb. Spavajući u vozu, prošla sam svoju stanicu works because I slept and I missed my stop. If the two actions have different subjects, you cannot use the -ći form; use a dok clause instead, which has its own subject: Dok sam spavala, voz je stao na granici (I slept, the train stopped).

Before writing a -ći form, ask: who does the main verb? If it is not the same person who does the -ći action, switch to dok + a normal verb. English lets "Reading the paper, the bus arrived" slip through; Serbian does not.

Forms that turned into other words

A few -ći forms have hardened into ordinary words. You already know zahvaljujući (thanks to), a preposition with the dative. Idući mostly means "next" before a noun (idući vikend). Recognise them; you do not build them.