In Polish, a clausal complement may be preceded by the propositional proform to. The presence of the proform to depends on the matrix verb: it may be obligatory, facultative, or excluded. The aim of the paper is to give an analysis of sentences with verbs excluding the proform to in terms of the semantic syntax (according to Stanisław Karolak’s theory of the predicate-argument structure of sentences and Andrzej Bogusławski’s theory of the operational grammar). There are three main semantic groups of verbs that take a clausal complement obligatorily without a proform: non-verbal communication verbs, verbs incorporating a contents argument, emotive verbs. The author claims that in all these cases a complement clause does not represent an argument of a predicate, but is a result of an operation.