Chapter XX On the Tenses
§ 573. Notwithstanding its name, the present tense in English, does not express a strictly present action. It rather expresses an habitual one. He speaks well=he is a good speaker. If a man means to say that he is in the act of speaking, he says I am speaking.
It has also, especially when combined with a subjunctive mood, a future power—I beat you (=I will beat you) if you don’t leave off.
§ 574. The English præterite is the equivalent, not to the Greek perfect but the Greek aorist. I beat=ἔτυψα not τέτυφα. The true perfect is expressed, in English, by the auxiliary have + the past participle.