vierittäessä

Vierittäessä is a Finnish verb form derived from the verb vierittää. It is the present adverbial participle (the -essa form) used to express a concurrent action, roughly corresponding to the English "while turning" or "during turning." In Finnish, such participial clauses are subordinating and modify the main clause, with the subject typically shared with the main clause unless otherwise indicated.

Formation and grammar: The form vierittäessä is built from the verb stem vierittä- plus the participial suffix -essä. This kind of participle provides a compact way to describe an action that takes place at the same time as the action in the main clause. Other related forms include the present active participle vierittävä (one who rotates) and the passive or perfect participles derived from the same verb, such as vieritetty, depending on voice and tense.

Usage: Vierittäessä is common in descriptive, technical, and instructional Finnish, where concise narration of processes is desired. It allows writers to link actions without additional conjunctions and to convey simultaneity or parallel steps within procedures or narratives. The exact sense of the clause depends on the sense of the main verb and the context in which the participle appears.

Example: Vierittäessä kappaletta havaittiin epätasaisuutta. (While rotating the piece, an irregularity was detected.)

See also: Finnish grammar, participles, vieritys (the noun form meaning rotation or turning).