A bolt can be stiff.Logical formLearned from6 sentences. A hand may get stiff.Logical formLearned from6 sentences. Polymers can be stiff.Logical formLearned from6 sentences. Heat can be stiff.Logical formLearned from6 sentences. A movement can be stiff.Logical formLearned from6 sentences. A current can be stiff.Logical formLearned from6 sentences. Tension can be stiff.Logical formLearned from6 sentences. A laugh can be stiff.Logical formLearned from6 sentences. A fur can be stiff.Logical formLearned from6 sentences. A canvas can be stiff.Logical formLearned from6 sentences. A shuffle can be stiff.Logical formLearned from6 sentences. Rules can be stiff.Logical formLearned from6 sentences. A frosting can be stiff.Logical formLearned from6 sentences. (Hiking boots) can be stiff.Logical formLearned from6 sentences. An upper lip can be stiff.Logical formLearned from6 sentences.