e written_. shall have
written_. written_.

2. It will be seen that the Present may express Undefined action or action
Going on; so also the Future. The Perfect likewise has a double use,
according as it denotes action Completed in present time (Present Perfect)
or Undefined action belonging to past time (Historical Perfect).

Principal and Historical Tenses.

258. Tenses which denote Present or Future time are called Principal (or
Primary) Tenses, those which denote Past time are called Historical (or
Secondary).

The Principal Tenses of the Indicative are: Present, Future, Present
Perfect, Future Perfect.

The Historical Tenses are: Imperfect, Historical Perfect, Pluperfect.

Present Indicative.

259. Besides the two uses indicated in the table, the Present Indicative
presents the following peculiarities:--

1. It is used to denote _a general truth_, i.e. something true not merely
in the present but at all times ('Gnomic Present'); as,--

virtus conciliat amicitias et conservat, _virtue establishes ties of
friendship and maintains them_ (i.e. always does so).

2. It is used of an attempted action ('Conative Present'); as,--

dum vitant vitia, in contraria currunt, _while they try to avoid_
(vitant) _vices, they rush into opposite ones_.

3. In lively narration the Present is often used of a past action
('Historical Present'); as,--

Caesar imperat magnum numerum obsidum, _Caesar demanded a large number
of hostages_ (lit. _demands_).

4. In combination with jam, jam diu, jam pridem, and similar words, the
Present is frequently used of an action originating in the past and
continuing in the present; as,--

jam pridem cupio te visere, _I have long been desiring to visit you_
(i.e. I desire and have long desired).

Imperfect Indicative.

260. 1. The Imperfect primarily denotes action _going on in past time_;
as,--

librum legebam, _I was reading a book_.

a. This force makes the Imperfect especially adapted to serve as the
tense of _description_ (as opposed to mere _narration_).

2. From the notion of action _going on_, there easily develops the notion
of _repeated_ or _customary_ action; as,--

legatos interrogabat, _he kept asking the envoys_;

C. Duilium videbam puer, _as a boy I often used to see Gaius Duilius_.

3. The Imperfect often denotes an attempted action ('Conative Imperfect')