An (iron frame) can be hollow.Logical formLearned from1 sentences. A (drilling bit) can be hollow.Logical formLearned from1 sentences. A coil can be hollow.Logical formLearned from1 sentences. A (cast iron cylinder) can be hollow.Logical formLearned from1 sentences. A cross section can be hollow.Logical formLearned from1 sentences. A speculation can be hollow.Logical formLearned from1 sentences. A grunting can be hollow.Logical formLearned from1 sentences. A hollow man can be stupid.Logical formLearned from1 sentences. A hollow man may be kept.Logical formLearned from1 sentences. A finger can be hollow.Logical formLearned from1 sentences. Paintings may look hollow.Logical formLearned from1 sentences. An opportunist can be hollow.Logical formLearned from1 sentences. Pratfalls may pertain-to a hollow man.Logical formLearned from1 sentences. (Brass gongs) can be hollow.Logical formLearned from1 sentences. Achievements of American democracy may ring hollow.Logical formLearned from1 sentences.