In this paper examples of synonymy and homonymy in Czech are presented. The sources of homonymy are exemplified by the morphological, syntactic and lexical means and their combinations in the sentence leading to their surface identity.
Synonymy is demonstrated by sentences with different syntactic and morphemic forms expressing the same meaning. Local adverbials with the meaning Where? (LOC) are analyzed here in a more detail.
Attention is focused on the analysis of the prepositional constructions with the preposition v(e) + Loc [in] and na + Loc [on] and the differences between the construction including them as well as examples of their interchangeability are demonstrated. Prepositional constructions with the preposition u + Gen [at/by] are added to the central domain of the local adverbials connected with the answer to the question Where? [LOC].
Criteria for the description of grammatical requirements for their form as well as for their lexicalized forms applied in this domain are proposed as the s