Lexical Verbs are basically the main verb‏‎ in a sentence. They carry some kind of real-world meaning and are sometimes actually known as the main verb:

You laughed.

I ran.

They are basically an open-class of verbs; in other words, we can add new verbs to this class‏‎. In recent years new additions to this class include:

She twerked in public.

I googled my answer.

So lexical verbs carry a semantic meaning. The only verbs not classed as lexical are auxiliary verbs‏‎, be, do, should, can, etc. These auxiliary verbs have a grammatical meaning (they talk about modality, voice, etc).

Using Lexical Verbs

Simple tenses use only a lexical verb:

{subject} + {lexical verb}

I run.

I walked.

Continuous or Perfect tenses use an auxiliary verb and a lexical verb.

{subject} + {auxiliary verb } + {lexical verb}

I had run.

I was walking.

In other words, a lexical verb can sit on its own but an auxiliary verb requires a lexical verb for it to make sense:

* She will in the garden.
She will sit in the garden.

* an asterisk is used to denote an ungrammatical sentence

Lexical Verbs in the TEFL Classroom

Do you need to teach your class about lexical verbs? The answer depends on your class but is probably, no. Many teachers will go through their professional life without mentioning it in the TEFL classroom. The only exception will be if you have a class who are particularly interested in grammar.

However, you will probably want your class to understand what an auxiliary verb is and you may well teach this. Just to differentiate between verbs you could always explain that there are auxiliary verbs and then all other verbs which are known as lexical verbs. Probably not worth going much further than that.

Useful Links

Auxiliary Verbs‏‎ – about those verbs which aren’t lexical verbs!