A track can be rugged.Logical formLearned from13 sentences. Trees may billow from a top of a rugged mountain.Logical formLearned from13 sentences. A (frontier city) can be rugged.Logical formLearned from13 sentences. A campaign can be rugged.Logical formLearned from13 sentences. A rugged island may conjure a mystique.Logical formLearned from13 sentences. A spot can be rugged.Logical formLearned from13 sentences. (Desert mountains) can be rugged.Logical formLearned from13 sentences. A (highland region) can be rugged.Logical formLearned from13 sentences. A (rebel stronghold) can be rugged.Logical formLearned from13 sentences. A location can be rugged.Logical formLearned from13 sentences. A (lawless area) can be rugged.Logical formLearned from13 sentences. A (quake zone) can be rugged.Logical formLearned from13 sentences. A northwestern region can be rugged.Logical formLearned from13 sentences. A pass can be rugged.Logical formLearned from12 sentences. A dissected plateau can be rugged.Logical formLearned from12 sentences.