Disks can be necessary.Logical formLearned from4 sentences. A string can be necessary.Logical formLearned from4 sentences. Identity can be necessary.Logical formLearned from4 sentences. (Capital punishment) can be necessary.Logical formLearned from4 sentences. Realization of peace can be necessary.Logical formLearned from4 sentences. A leader can be necessary for the future of a country.Logical formLearned from4 sentences. Some domains can be necessary.Logical formLearned from4 sentences. Holes can be necessary.Logical formLearned from4 sentences. A phenomenon can be necessary.Logical formLearned from4 sentences. Banks can be necessary.Logical formLearned from4 sentences. Criteria can be necessary for an introduction of a concept.Logical formLearned from4 sentences. (Succession plans) can be necessary.Logical formLearned from4 sentences. A procedure may be made necessary by a fact.Logical formLearned from4 sentences. Involvement can be necessary.Logical formLearned from4 sentences. Distances can be necessary.Logical formLearned from4 sentences.