According to Pottier, Greimas and Coseriu, lexical meaning can be analyzed into sememes. Sememes are the units which correspond to the distinctive features in phonology. The methods by which we analyze the meanings of lexemes are approximately the same as the ones by which we analyze phonemes. We adopt the approach from the functional-structural point of view in semantics. Many scholars think that the methods mentioned above can be applied to the study of lexical meaning. However, we cannot but be confronted with difficult problems which cannot be overlooked. Namely, the number of units to be studied in lexematics is enormous while the number of units in phonology and grammar is much limited. Thus, one cannot but decrease the number of units to be dealt with. On has to exclude the units that cannot be structuralizable from the object of study. Eugenio Coseriu presents a criterion by which the units are excluded from consideration: terminology, metalanguage, repeated discourse are to be excluded.