Neglected for decades, learning and teaching vocabulary has gained a great importance both in native and foreign language acquisition as one of the central components of the process. As stressed by McCarthy (1990), there is no meaningful means of expression in communication without words, regardless of the level of mastery of the other sub-skills.
Assimilation of the basic unit of a language system, namely a word, starts with the acquisition of the combination of its sound pattern with the meaning it denotes. Yet, as such, it does not constitute communication. It is due to the diverse semantic and structural properties of words that they can be combined into more complex utterances, thus accounting for speech acts. Those features listed by Schmitt and McCarthy  involve:

  • the form – either oral or written,
  • the meaning – affective / connotative, referential (homonyms / homophones, metaphorical uses), or pragmatic (situational appropriateness),
  • the morphology,
  • lexical relations, including collocations, synonymy, antonymy, hypo- and hyperonymy,
  • syntactic properties.

The greater the mastery of all of those features, the higher the level of proficiency of a learner. On the other hand, such multitude of information about each single word automatically constitutes difficulties to the students who are to learn a new item. Therefore, it is important to build vocabulary on a systematic basis.