A blackness can be hollow.Logical formLearned from4 sentences. A statement may sound hollow.Logical formLearned from4 sentences. Rectangles can be hollow.Logical formLearned from4 sentences. A group can be hollow.Logical formLearned from4 sentences. Entertainment can be hollow.Logical formLearned from4 sentences. A muscle can be hollow.Logical formLearned from4 sentences. A (fiber membrane filtration) can be hollow.Logical formLearned from4 sentences. Birds can be hollow.Logical formLearned from4 sentences. Processes can be hollow.Logical formLearned from4 sentences. An issue can be hollow.Logical formLearned from4 sentences. A hand can be hollow.Logical formLearned from4 sentences. Fangs can be hollow.Logical formLearned from4 sentences. A whisper can be hollow.Logical formLearned from4 sentences. Boards can be hollow.Logical formLearned from4 sentences. A stage can be hollow.Logical formLearned from4 sentences.