He did not.
Albus Dumbledore died after Severus Snape hit him with the killing curse. Dumbledore had previously told Snape that when the time came, it must be Snape who killed him. This was to prevent Draco Malfoy from having to do so and to also ensure that Dumbledore died the last master of the Elder wand. However, as Draco disarmed Dumbledore, that part of the plan failed.
Yes, he made the Unbreakable Vow with Draco's mother, Narcissa Malfoy, in the "Spinner's End" chapter of Harry Potter and the Half-Blood Prince. He promised to watch over Draco and keep him safe, to help Draco with his task (killing Dumbledore), and to kill Dumbledore himself if Draco couldn't do it.
She visited him to see if he knew what the Dark Lord wanted her son Draco to do && if the Dark Lord wanted Snape to carry on the task if Draco failed also she wanted Snape to make the Unbreakable Vow && help Draco so he would not be hurt.
In Harry Potter and the Half-Blood Prince, Severus Snape and Narcissa Malfoy performed the Unbreakable Vow. This is the ultimate magical promise, as if Snape chose to break this promise, he would die. Snape promised whilst holding hands with Narcissa and with the Bonder (witness) Bellatrix Lestrange, that he would assist Draco Malfoy in his task of killing Albus Dumbledore if Malfoy struggles or is in danger of failing. Snape obliged willingly, as Dumbledore and Snape has already planned Dumbledore's death.
No, Severus Snape did.
Severus Snape or Draco Malfoy
No, Severus Snape is.
severus snape
no,snape made a promise to watch over Draco malfoy inthe sixth book,as Draco was given a dangerous task by voldemort which everyone was sure he would die attempting it dumbeldore himself told snape to take the task to watch over Draco
Well, Harry only hit snape because Sirius was trying to talk to him but Snape wouldn't let him.
Snape pairs Harry up with Draco to duel, though Gilderoy had wanted Harry to duel Ron. Snape's choice in putting Harry and Draco together turns out badly, causing the school to realize Harry is a Parseltongue.
Albus Dumbledore was killed by Severus Snape. Although Dumbledore, who was dying anyway, had already arranged for Snape to kill him so that Draco Malfoy wouldn't have to and so that the Elder wand would not change masters. However, as Draco disarmed Dumbledore shortly before his death that part of the plan did not work.