A (sound chamber) can be hollow.Logical formLearned from2 sentences. A (swing arm) can be hollow.Logical formLearned from2 sentences. A greed can be hollow.Logical formLearned from2 sentences. A football can be hollow.Logical formLearned from2 sentences. A terminal can be hollow.Logical formLearned from2 sentences. Montrals can be hollow.Logical formLearned from2 sentences. (Copper pipes) can be hollow.Logical formLearned from2 sentences. An inside of a pagoda can be hollow.Logical formLearned from2 sentences. A property can be hollow.Logical formLearned from2 sentences. (Charge weapons) can be hollow.Logical formLearned from2 sentences. A frenzy can be hollow.Logical formLearned from2 sentences. Workpieces can be hollow.Logical formLearned from2 sentences. Maxillaes can be hollow.Logical formLearned from2 sentences. Ponds can be hollow.Logical formLearned from2 sentences. A (silver dollar) can be hollow.Logical formLearned from2 sentences.