The phrase "drum into" means to teach or emphasize something repeatedly until it is well understood or remembered. Here are some synonyms for this phrase: instill, establish, ingrain, impress, inculcate, hammer in, drive home, drill in, engrave, etch, fix, plant, seed, lodge. All of these words imply a sense of repeated emphasis or forceful repetition in order to ensure that an idea or concept is firmly rooted in someone's mind. Whether you're trying to teach a lesson or impart an important point, using one of these synonyms for "drum into" can help you convey the urgency and importance of your message.