1 He asked her for the key of the schoolroom.
2 He had the key, and no one else could enter it.
3 Having reached the door, he turned the key and opened it.
4 As he was going downstairs, he heard the key being turned in the lock.
5 As the door closed, Dorian put the key in his pocket and looked round the room.
6 Then he took out the key and returned to the room, locking himself in as he did so.
7 When they reached the top landing, Dorian took out the key and turned it in the lock.
8 When the sound of their footsteps had died away, Dorian locked the door and put the key in his pocket.
9 "And here is the key, sir," said the old lady, going over the contents of her bunch with tremulously uncertain hands.
10 When they reached the top landing, Dorian set the lamp down on the floor, and taking out the key, turned it in the lock.
11 Dorian said nothing, but rose from the table, and passing into the next room, sat down to the piano and let his fingers stray across the white and black ivory of the keys.