Diagramming Verbs with Auxiliaries

Verbs in English often take "auxiliaries" (often, forms of the verbs to be, to do, or to have).  Normally, in diagramming, a verb with its auxiliaries is treated as a single unit.

In these examples, the auxiliaries had and will have been are used to express tense and voice (active or passive).  In the first example, had repeated is called the "past perfect" tense, and in the second example, will have been sold is called the "future perfect passive."

English also has so-called "modal" auxiliaries (would, should, ought, must, might, and so on), and "progressive" tenses expressed by auxiliary verbs (in the following example, going to be).

Participles, gerunds, and infinitives, as verbals, can also have auxiliaries.  Infinitives (the to-form of the verb) are treated as single units.

Sometimes, modifying elements come between the auxiliary and its verb, or between the to and the verb in an infinitive (the dreaded "split infinitive," which in some constructions nowadays is more widely tolerated than it used to be).  This kind of construction requires bridging in diagramming.

The auxiliary to do, like the auxiliary to have, is used to form questions.  To do also appears in negations.  For a fuller treatment of to do in its employment as an auxiliary, see the discussions of diagramming questions and diagramming negations.

Click here to return to the list of special problems.

Click here to return to the "Syntax" home page.