Lily complained to the book seller that there were several pages ________ in the dictionary.
句意：莉莉向卖书的人抱怨说字典里缺了几页。miss错过； 想念；缺失（常用主动形式）。lose使迷路；错过；缺少（常用被动 形式）。drop滴落；下降。leak泄露。因此，本题的正确答案为B。