A summit can be necessary.Logical formLearned from8 sentences. A (sea change) can be necessary.Logical formLearned from8 sentences. A court can be necessary.Logical formLearned from8 sentences. Arrests can be necessary.Logical formLearned from8 sentences. Transfers can be necessary.Logical formLearned from8 sentences. Reforms can be necessary for an establishment of democracy.Logical formLearned from8 sentences. A veto can be necessary.Logical formLearned from8 sentences. Battles can be necessary.Logical formLearned from8 sentences. Existence can be necessary.Logical formLearned from7 sentences. Reform of a system can be necessary.Logical formLearned from7 sentences. A legal action can be necessary.Logical formLearned from7 sentences. Sterilization can be necessary.Logical formLearned from7 sentences. An improvement of relations can be necessary.Logical formLearned from7 sentences. A concession can be necessary.Logical formLearned from7 sentences. Presence of forces can be necessary.Logical formLearned from7 sentences.