721. The person ending limits the meaning of the stem by pointing out
the person of the subject. There are three PERSONS, the _First_, used of
the speaker, the _Second_, of what is spoken to, and the _Third_, of
what is spoken of. The person ending furthermore indicates number and
voice.
722. There are two NUMBERS: the _Singular_, used of one, and the
_Plural_, used of more than one.
723. There are two VOICES: the _Active_, indicating that the subject
acts, and the _Passive_, indicating that the subject acts on himself, or
more commonly is acted on by another.
724. Only transitive verbs have all persons of the passive. Intransitive
verbs have in the passive only the third person singular, used
impersonally; the participle in this construction is neuter.
725. Some verbs have only the passive person endings, but with a
reflexive or an active meaning; such are called _Deponents_: see 798.