(Plastic strips) can be stiff.Logical formLearned from2 sentences. A stiff upper lip can be in_the_face_of adversity.Logical formLearned from2 sentences. (Leather collars) can be stiff.Logical formLearned from2 sentences. A jump can be stiff.Logical formLearned from2 sentences. Fillings can be stiff.Logical formLearned from2 sentences. Appearances can be stiff.Logical formLearned from2 sentences. Caps can be stiff.Logical formLearned from2 sentences. A southwesterly can be stiff.Logical formLearned from2 sentences. A pining can be stiff.Logical formLearned from2 sentences. A royal protocol can be stiff.Logical formLearned from2 sentences. An attitude may keep a stiff upper lip.Logical formLearned from2 sentences. A stiff upper lip may hide a gap.Logical formLearned from2 sentences. A (hip joint) can be stiff.Logical formLearned from2 sentences. A (fingernail brush) can be stiff.Logical formLearned from2 sentences. Performance can be stiff.Logical formLearned from2 sentences.