[She can't help but glare a little. The old fox didn't follow the path of chivalry, so he didn't always tell the truth. But if was going to keep playing this game, she might was well indulge him. Besides, he might be 'testing' her, as annoying as the prospect was. She suppressed a sigh and rattled off the 'lessons'.]

Naturally, I am incapable of summoning you... you are still human. Had you been a Servant, I would have been able to sense your approach, with the exception of the Assassin class, which is capable of concealing his presence. A Servant is a Heroic Spirit summoned by a magus chosen by the Holy Grail as a Master, who then orders his Servant to fight on his behalf with the other six Servants until only one Master and Servant remain.

[She held up her right hand, the back facing out]

Masters are recognised by the three seals they bear on the backs of their right hands, used to issue an order which a Servant cannot disobey. When all three are depleted, the Master loses his connection to his Servant and that Servant disappears and returns to the Throne of Heroes.

[Her expression is expectant, as if to say, "Well, did I pass"?]