Contextuality or grammaticalty? In the process of communication participants may contravene grammatical rules or their utterance may have reference to mistaken context. Prosperous communication may be impeded by both. Conning and adherence of certain grammaticai conventions present difficulty for language-Iearners. It may be typical by learning - for examples - small Finno-Ugrian languages, that description of these languages are not rule-centric enough. The main question of this paper is that if it is possible to avoid making ungrammatical sentences (because of an unexplained grammar) by using a correctly described rule in pursuance of which context may get injured. Presented examples (usage of Udmurt accusative) suggest that communicative disorders made by injuring of context are easier superable then disorders made by using ungrammatical structures.