A list of operators may be grouped into levels of operators.Logical formLearned from10 sentences. An operator may pertain-to a (rail line).Logical formLearned from10 sentences. An operator can be blind.Logical formLearned from10 sentences. Operators may be trained.Logical formLearned from10 sentences. An operator may pertain-to a consortium.Logical formLearned from10 sentences. Eigenvalues may pertain-to an operator.Logical formLearned from10 sentences. Operators may recognize that something-is-the-case.Logical formLearned from10 sentences. An operator may be used.Logical formLearned from10 sentences. An operator may undergo an implementation.Logical formLearned from10 sentences. An operator may agree.Logical formLearned from10 sentences. An (airport operator) can be in a country.Logical formLearned from10 sentences. A (machine operator) can be trapped.Logical formLearned from10 sentences. An operator may pertain-to a (pipeline system).Logical formLearned from10 sentences. Operators can be in a number of developing markets.Logical formLearned from10 sentences. A head may pertain-to a (rail operator).Logical formLearned from10 sentences.