From the shelter of the doorway he watched him go up the steps of a particularly evil-looking house and rap sharply, with a peculiar rhythm, on the door.
He always knocks on doors with a peculiar rhythm.
mnli hypothesis: He always knocks on doors with a peculiar rhythm. premise: From the shelter of the doorway he watched him go up the steps of a particularly evil-looking house and rap sharply, with a peculiar rhythm, on the door.