A hummer can be rugged.Logical formLearned from8 sentences. Warheads can be rugged.Logical formLearned from7 sentences. A (mountain chain) can be rugged.Logical formLearned from7 sentences. Ice can be rugged.Logical formLearned from7 sentences. A spine can be rugged.Logical formLearned from7 sentences. Outdoor pursuits can be rugged.Logical formLearned from7 sentences. A sound can be rugged.Logical formLearned from7 sentences. Formations can be rugged.Logical formLearned from7 sentences. An airframe can be rugged.Logical formLearned from7 sentences. Outdoorsmen can be rugged.Logical formLearned from7 sentences. A sense can be rugged.Logical formLearned from7 sentences. Roots can be rugged.Logical formLearned from7 sentences. A craft can be rugged.Logical formLearned from7 sentences. Health can be rugged.Logical formLearned from7 sentences. Realities can be rugged.Logical formLearned from7 sentences.