Quid autem fit coruscatio et unde proveniat, diversi diversimode tradiderunt. Dixit enim Empedocles quod coruscatio est ignis occultatus in nubibus ex radiis solis. Et hoc, dicit Aristoteles, esse falsum, quia si hoc esset, ex omni nube coruscatio accideret, quia in omni nube radii solares occultantur. Anaxagoras autem dixit quod coruscatio est ex aere descendente in nubem vel ad nubem, et se in ea occultante, cuius apparitio est coruscatio, et quando ille ignis extinguitur in nubibus aquosis, stridor illius extinctionis vocatur tonitruum.

In the above passage, we see Et hoc, dicit Aristoteles, esse falsum... (And this, Aristotle says, is false...) Note that the verb esse is an infinitive and its subject hoc is in the accusative. This indicates an indirect statement, since we do not have the direct words of Aristotle, but rather: "Aristotle says that this is false."

The tense of the infinitive in an indirect statement depends upon the tense of the main verb in the sentence. Action in an indirect statement happening at the same time as a main verb requires the use of a present infinitive. Time before the main verb requires a perfect infinitive, and time after the main verb, a future infinitive. For example:

Aristoteles dicit hoc esse falsum. (Aristotle says this is false.)

Aristoteles dicit hoc fuisse falsum. (Aristotle says this was false.)

Aristoteles dicit hoc futurus esse falsum. (Aristotle says this will be false.)

Aristoteles dixit hoc esse falsum. (Aristotle said this was false.) [same time as main verb, which is in the perfect tense] etc.

Make this exercise printable