A (steel bar) can be hollow.Logical formLearned from2 sentences. A competition may look hollow.Logical formLearned from2 sentences. A slogan may ring hollow.Logical formLearned from2 sentences. A (milk chocolate egg) can be hollow.Logical formLearned from2 sentences. A (control room) can be hollow.Logical formLearned from2 sentences. A reassurance may ring hollow.Logical formLearned from2 sentences. An extravaganza can be hollow.Logical formLearned from2 sentences. A righteousness can be hollow.Logical formLearned from2 sentences. Meditations can be hollow.Logical formLearned from2 sentences. A (classroom slogan) may ring hollow.Logical formLearned from2 sentences. Mansions can be hollow.Logical formLearned from2 sentences. A spear can be hollow.Logical formLearned from2 sentences. A wire can be hollow.Logical formLearned from2 sentences. A hollow tree can be on a mountainside.Logical formLearned from2 sentences. A (rallying call) can be hollow.Logical formLearned from2 sentences.