Morphologically marked Aktionsarten (‘modes-of-action’) in Russian may be derived from unmarked source verbs. The resulting verbs’ meaning can be specified by creating new lexemes by means of prefixation and suffixation. These lexemes and their respective morphological operations can be systematicised in extensive networks. As will be shown in this thesis, illustrations of such networks can make a foundation for deeper studies of semantic changes that accompany these operations. Through concrete examples of Russian verbs we will uncover how thorough simplifications in foreign language learning books can point out the wrong path in the process of obtaining a foreign language.