They also have lexical aspect (perfective and imperfective), voice, nine tenses, three moods,[note 1] four evidentials and six non-finite verbal forms.
As is typical of Slavic languages, Bulgarian verbs express lexical aspect (вид).
Newly adopted verbs, especially from English, tend to take a –ирам (–iram) ending, in which case they only have one form (the imperfective).
Its most common use is in story telling to provide a background to other actions which are usually expressed with verbs in the past aorist.
Although imperfective and perfective verbs are conjugated in the same way in the past aorist, there is difference in their meaning.
Compare the sentences: Usually the difference between the two tenses is very clear: But imperfective verbs both in past imperfect and past aorist can express actions that have long duration and therefore both tenses can be used to say that one action happened at the same time as another.
Compare the sentences (they all contain the imperfective verb играя that expresses an action with some duration, but depending on the tense the sentences have different meaning): Present perfect (in Bulgarian минало неопределено време, past indefinite tense) expresses an action which happened in the past, but the precise moment when it happened is not specified.
In other words, the corresponding indefinite forms of the participle (masculine, feminine, neuter, singular, plural) are used according to the gender and number of the subject.
Example (чета, to read): In contrast with English, in Bulgarian (very rarely) the present perfect can be used even if the moment when the action happened is specified.
Example (чета, to read): Rarely the past perfect can be used for actions that happened at an indefinite time in the past but very long ago, especially in sentences containing the phrase "someone sometimes said": The future tense (in Bulgarian бъдеще време) is formed with the particle ще (derived from the verb ща, "to want") and the present simple tense (ще always stands before the present forms).
Negation is expressed with the construction нямаше да + the present tense, although forms with не are also possible but found mainly in the poetry.
Example (чета, to read): The voice in Bulgarian adjectives is presented not through the auxiliary verb, as it is in English ("I have eaten" – active; "I was eaten" – passive), but rather by the ending on the past participle; the auxiliary remains съм ("to be"): Modal distinctions in subordinate clauses are expressed not through verb endings, but through the choice of complementizer – че (che) or да (da) (which might both be translated with the relative pronoun "that").
[2] It is formed by a special form[note 3] of the auxiliary 'съм' (to be), and the aorist active participle of the main verb:[3] Bulgarian verbs are inflected not only for aspect, tense and modality, but also for evidentiality, that is, the source of the information conveyed by them.
[4][5] This can be illustrated with the four possible ways of rendering in Bulgarian the English sentence 'The dog ate the fish' (here AORPT denotes the aorist active participle): Indicative: Ку̀четоkuče-todog-DEFизя̀деizjad-eeat-AOR.3sgрѝбатаriba-tafish-DEFКу̀чето изя̀де рѝбатаkuče-to izjad-e riba-tadog-DEF eat-AOR.3sg fish-DEF"I know from my own observation that the dog ate the fish.
"Inferential: Ку̀четоkuče-todog-DEFеebe.3sgизя̀лоizjal-oeat.AORPT-N.SGрѝбатаriba-tafish-DEFКу̀чето е изя̀ло рѝбатаkuče-to e izjal-o riba-tadog-DEF be.3sg eat.AORPT-N.SG fish-DEF"The dog must have eaten the fish."
)Renarrative: Ку̀четоkuče-todog-DEFизя̀лоizjal-oeat.AORPT-N.SGрѝбатаriba-tafish-DEFКу̀чето изя̀ло рѝбатаkuče-to izjal-o riba-tadog-DEF eat.AORPT-N.SG fish-DEF"I've been told that the dog ate the fish.
"Dubitative: Ку̀четоkuče-todog-DEFбило̀bil-obe.AORPT-N.SGизя̀лоizjal-oeat.AORPT-N.SGрѝбатаriba-tafish-DEFКу̀чето било̀ изя̀ло рѝбатаkuče-to bil-o izjal-o riba-tadog-DEF be.AORPT-N.SG eat.AORPT-N.SG fish-DEF"I've been told that the dog ate the fish, but I doubt it."
Kutsarov, for example, posits a separate category, which he terms 'type of utterance' (вид на изказването), proper to which is only the distinction between forms expressing speaker's own statements (indicative, inferential), and forms that retell statements of another (renarrative, dubitative).
[8] Another view is presented by Gerdzhikov – in his treatment there are two distinctive features involved – subjectivity and renarrativity.
[11] The dubitative is formed from the renarrative by adding the past active participle of the verb съм (to be).
Past active aorist participle (минало свършено деятелно причастие) is used to form the present perfect, in the renarrative and conditional mood and as an adjective.