A stratification can be rigid.Logical formLearned from10 sentences. (Class distinctions) can be rigid.Logical formLearned from10 sentences. A point can be rigid.Logical formLearned from10 sentences. An (examination system) can be rigid.Logical formLearned from10 sentences. A language can be rigid.Logical formLearned from10 sentences. A head can be rigid.Logical formLearned from10 sentences. A self-discipline can be rigid.Logical formLearned from10 sentences. Domains can be rigid.Logical formLearned from10 sentences. A bearing can be rigid.Logical formLearned from10 sentences. An economic system can be rigid.Logical formLearned from10 sentences. A quota can be rigid.Logical formLearned from10 sentences. A racial segregation can be rigid.Logical formLearned from10 sentences. A consistency can be rigid.Logical formLearned from10 sentences. An outline can be rigid.Logical formLearned from10 sentences. A series can be rigid.Logical formLearned from10 sentences.