s the subject
in the passive voice, the direct object is known as the _retained object:_
[He was paid nine _dollars_ by John].

+67. Infinitives.+--The infinitive form of the verb is often called a
verbal noun, because it partakes of the nature both of the verb and of the
noun. It is distinguished from the _finite_, or true, verb because it does
not make an assertion, and yet it assumes one. While it has the modifiers
and complements of a verb, it at the same time has the uses of a noun.

There are two infinitives: the _root infinitive_ (commonly preceded by
_to_, the so-called _sign_ of the infinitive), and the _gerund_, or
_infinitive in -ing_.

1. Root infinitive: [_To write_ a theme requires practice].

2. Gerund: [_Riding_ rapidly is dangerous]. In each of these sentences
the infinitive, in its capacity as noun, stands as the subject of the
sentence. In 1, _to write_ shows its verb nature by governing the object
_theme;_ in 2, _riding_ shows its verb nature by taking as a modifier the
adverb _rapidly_.

Each form of the infinitive is found as the subject of a verb, as its
object, as an attribute complement, and as the object of a preposition.
The root infinitive, together with its subject in the objective case, is
used as the object of verbs of knowing, telling, etc.: [I know _him to be
a good boy_]. See also Appendix 85 for adjective and adverbial uses.

The infinitive has two tenses: the _present_ and the _perfect_. The
_present_ tense denotes action which is not completed at the time of the
principal verb: [He tries _to write_. He tried _to write_. He will try _to
write_]. The _perfect_ infinitive denotes action complete with reference
to the time of the principal verb: [I am glad _to have known_ her].

+68. Participles.+--Participles are verbal adjectives: [The girl _playing_
the piano is my cousin]. _Playing_, as an _adjective_, modifies the noun
_girl_; it shows its _verbal_ nature by taking the object _piano_.

The _present participle_ ends in _-ing_. When the _past participle_ has an
ending, it is either _-d, -ed, -t_, or _-en_. The _perfect participle_ is
formed by combining _having_ with a past participle; as, _having gone_.

There is danger of confusing the present participle with the gerund, or
infinitive in _-ing_, unless the adjective character of the one and the
noun character of the other are clearly distinguished: [The boy, _driving_
the cows to pasture, was performing his daily task (p