As the analyzed material shows, sentences with an accompanying subject appeared as early as in Old Polish. The verb in such sentences came to double consensus with the subject about its form. When the person named by the accompanying subject was of minor importance, the verb adjusted its form with the main subject (e.g. Ojciec z synem wszedl - The father and the son came in). However, when the accompanying subject was as important as the main agent of action, the verb adjusted its form to either of the subject (e.g. Ojciec z synem wyszli). The tendency is also visible in contemporary Polish.
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