Ключевые слова: address, apartment, arrangement, bill, box, communication, company, condominium, confidential, confidentiality, contact, corporation, correspondence, courier, delivery, detail, drawer, drop, envelope, hole, insert, key, keyhole, letter, letterbox, line, lock, locker, mail, mailbox, many, message, number, office, pattern, perspective, post, postal, postbox, privacy, private, public, row, safe, secure, security, send, slot, sort, storage, tidy, wall,