(1) The significance of the tenses of the Indicative mood may be stated in general as follows: –
As respects progress:
The Present and Imperfect denote action in progress; the Perfect, Pluperfect, and Future Perfect denote completed action; the Aorist represents the action indefinitely as an event or single fact; the Future is used either of action in progress like the Present, or indefinitely like the Aorist.
As respects time:
The Present and Perfect denote present time; the Imperfect, Aorist, and Pluperfect denote past time; the Future and Future Perfect denote future time.
(2) The tenses of the Indicative in general denote time relative to that of speaking. Most exceptions to this rule are apparent or rhetorical rather than real and grammatical. In indirect discourse the point of view, as respects time, of the original speaking or thinking is retained. Of two verbs of past time, one may refer to an action antecedent to the other, but this fact of antecedence is implied in the context, not expressed in the tense. By prolepsis also a verb of past time may refer to or include events to take place after the time of speaking, but before a point of future time spoken of in the context. In conditional sentences of the second form, the tenses are properly timeless.