Shells can be hollow.Logical formLearned from134 sentences. Words may ring hollow.Logical formLearned from131 sentences. Spheres can be hollow.Logical formLearned from129 sentences. Stems can be hollow.Logical formLearned from128 sentences. A laugh can be hollow.Logical formLearned from124 sentences. A cemetery can be hollow.Logical formLearned from115 sentences. A heart can be hollow.Logical formLearned from115 sentences. An interior can be hollow.Logical formLearned from113 sentences. A road can be hollow.Logical formLearned from110 sentences. A center can be hollow.Logical formLearned from109 sentences. A gesture can be hollow.Logical formLearned from106 sentences. A stem can be hollow.Logical formLearned from102 sentences. An organ can be hollow.Logical formLearned from99 sentences. Eyes can be hollow.Logical formLearned from99 sentences. Cylinders can be hollow.Logical formLearned from91 sentences.