Text linguistics: from sentence to text. Defining the terms "sentence" and "text". The notion of "textuality". Lexical semantics is the study of word meaning. Descriptively speaking, the main topics studied within lexical semantics involve either the internal semantic structure of words, or the semantic relations that occur within the vocabulary. Werlichin's earlier comment (1976:14): "sentence grammars do not tell the learner of a foreign language the whole story about communication by means of language".