Obstacles can be intractable.Logical formLearned from17 sentences. Obstacles can be to a (peace agreement).Logical formLearned from17 sentences. An obstacle can be to a victory.Logical formLearned from17 sentences. Obstacles can be subtle.Logical formLearned from17 sentences. An obstacle can be to peace.Logical formLearned from17 sentences. Obstacles may be cleared.Logical formLearned from17 sentences. An obstacle can be a fear.Logical formLearned from17 sentences. Unemployment may remain an obstacle.Logical formLearned from17 sentences. An obstacle can be to cooperation.Logical formLearned from17 sentences. A government can be an obstacle.Logical formLearned from17 sentences. An obstacle can be in advance of a (weekend visit).Logical formLearned from17 sentences. An obstacle can be to economic reform.Logical formLearned from17 sentences. Language can be an obstacle.Logical formLearned from17 sentences. Obstacles can be to a goal.Logical formLearned from17 sentences. Obstacles can be to commerce.Logical formLearned from17 sentences.