A male may scrape knuckles.Logical formLearned from6 sentences. A female may rub knuckles.Logical formLearned from6 sentences. A knuckle can be on a finger.Logical formLearned from5 sentences. Knuckles may pertain-to a user.Logical formLearned from5 sentences. Knuckles may tingle.Logical formLearned from5 sentences. Knuckles may heal.Logical formLearned from5 sentences. Knuckles may be cracked.Logical formLearned from5 sentences. A knuckle may pertain-to a forefinger.Logical formLearned from5 sentences. (Album brass knuckles) may pertain-to a female.Logical formLearned from5 sentences. A tightening can be visible in whites of knuckles.Logical formLearned from5 sentences. Knuckles can be cracked.Logical formLearned from5 sentences. Knuckles may crack across a (cheek bone).Logical formLearned from5 sentences. A person may rub a knuckle on a head.Logical formLearned from5 sentences. Blood can be from knuckles.Logical formLearned from5 sentences. A male may brush a knuckle.Logical formLearned from5 sentences.