Fliers may challenge a (surveillance flight).Logical formLearned from9 sentences. A lawyer may challenge a (state law).Logical formLearned from9 sentences. A male may challenge champion.Logical formLearned from9 sentences. A person may challenge a finding of death.Logical formLearned from9 sentences. Some candidates may challenge a layout of a ballot.Logical formLearned from9 sentences. A world-city may challenge neighbors.Logical formLearned from9 sentences. A person may challenge a law.Logical formLearned from9 sentences. Relations may be challenged.Logical formLearned from9 sentences. A political-leader may be challenged by (opposition leader).Logical formLearned from9 sentences. A result may be challenged.Logical formLearned from9 sentences. Lawyers may challenge evidence.Logical formLearned from9 sentences. Lawyers may challenge an order.Logical formLearned from9 sentences. Work may challenge a notion.Logical formLearned from9 sentences. Protesters may challenge a re-election of a male.Logical formLearned from9 sentences. (World leaders) may challenge a legitimacy.Logical formLearned from9 sentences.