3. Intransitive Verbs may be used impersonally in the passive; as,—
curritur, people run (lit. it is run);
ventum est, he (they, etc.) came (lit. it was come).
TENSES.
TENSES OF THE INDICATIVE.
[257]. 1. The Latin tenses express two distinct notions:—
a) The period of time to which the action belongs: Present, Past, or Future.
b) The kind of action: Undefined, Going on, or Completed.
The Latin with its six tenses is able to express each of the three kinds of action for each of the three periods of time (making practically nine tenses). It does this by employing certain tenses in more than one way, as may be seen by the following table:—
| KIND OF ACTION. | PERIOD OF TIME. | ||
| PRESENT. | PAST. | FUTURE. | |
| UNDEFINED | Present: scrībō, I write. | Historical Perfect: scrīpsī, I wrote. | Future: scrībam, I shall write. |
| GOING ON. | Present: scrībō, I am writing. | Imperfect: scrībēbam, I was writing. | Future: scrībam, I shall be writing. |
| COMPLETED. | Present Perfect: scrīpsī, I have written. | Pluperfect: scrīpseram, I had written. | Future Perfect: scrīpserō, I shall have 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).