The first major distinction that must be made when evaluating word knowledge is whether the knowledge is productive or receptive; even within those opposing categories, there is often no clear distinction. Words that are generally Understood when heard or read or seen constitute a person's receptive vocabulary. These words may range from well-known to barely known. A person's receptive vocabulary is the larger of the two. The productive vocabulary to be larger than the receptive vocabulary, Productive vocabulary, therefore, generally refers to words that can be produced within an appropriate context and match the intended meaning of the speaker or signer. As with receptive vocabulary, however, there are many degrees at which a particular word may be considered part of an active vocabulary. Knowing how to pronounce, sign or write a word does not necessarily mean that the word that has been used correctly or accurately reflects the intended message; but it does reflect a minimal amount of productive knowledge.