Abstract
The Slavic languages have many similarities according to their genetic relationships, reciprocal influences and similar external influences. Polish and Russian use the infinitive verbal forms most active.
Polish is in this aspect very close to the East Slavic languages. The infinitive was lost or his usage is very limited in the South Slavic area, it was replaced with a construction with the particle da.
Infinitive has many model function in the East-Slavic languages and in Polish. The Verbal nouns are in the West-Slavic languages a part of the verbal system, on the other hand they have a non-verbal character in the East-Slavic languages and in most of the South-Slavic languages is their character ambiguous.
The l-participle is paradigmatic in Bulgarian, Belorussian and partially in Ukrainian. In the West-Slavic languages compete this participles to the -n/-t- participles.