The process of vocabulary acquisition is complex. Knowing a word goes beyond knowing only its more frequent meaning.
Nation (1990) and Richards (1976) claim that for knowing a word, it is necessary to know its orthographical and phonological form, meaning, grammatical aspect, associations, collocations, frequency and register (in Schmidt & McCarthy, 1997, p.4).
Folse (2007) adds other aspects that include polysemy (several meanings for the same word), connotation (actual meaning) and denotation (idea suggested in a context).
Nation (2001) also provides a set of aspects of what is involved in knowing a word presented in the table below
R=receptive knowledge, P=productive knowledge
Thus, if the teacher wants her/his students to know a word, then s/he has to consider all the features of the word and design tasks that enhance both types of knowledge.
So, anytime the teacher wants to present a new word, s/he has to do further research about all of the features of that word or set of words before planning the lesson