In plain words
She feels no anger that he seized and killed her sons; the child-killer she tells us to let go, the foolish Draupadī; is this fellow a brahmin? Why let him go? Kill him, then; if you do not kill him, with my fist's blow I shall split his head; watch, all of you.
‘Draupadī has gone mad because her sons are dead. Otherwise, would she take hold of this sinner's feet? Let go of him! I shall smash his head with my fist,’ he said, shaking with fury. Then Draupadī spoke good, calming words. Arjuna too: ‘My word will be broken. So it is not possible to forgive him,’ he decided. Then she meditated on Kṛṣṇa. She told a way out:
The son of Indra, praised by the world, the great hero, with his dreadful sword cut off Aśvatthāmā's locks and the great jewel within his crown of hair, took it, so that his lasting fame shone; the bonds of the many ropes he undid in good faith, and thrust him out to leave the ground of the camp.
She taught further, like this:
One who is afraid, one who is distressed in misery, one who in sleep his body has forgotten, one who in ease has drunk liquor, one who, beaten, has fled, one of good and simple nature, one who ‘Save me!’ cries out, and a woman: to kill them is not Dharma, Arjuna!
‘To cut him to pieces because he has fallen into our hands is not good. It is against our very kṣatriya Dharma. As much as it pains me that my sons have been killed, if that Aśvatthāmā is killed his mother too will suffer as I do, will she not! My sons who have died are dead in any case. Now, in no way will my sons come back. Why should we cause another mother pain? Stop!’ she said. Draupadī's chief quality: forbearance. Draupadī protected and sustained all the Pāṇḍavas to the very end, and spread fame through the whole world.