Obstacles can be in a case.Logical formLearned from9 sentences. An obstacle can be a requirement.Logical formLearned from9 sentences. Obstacles may hinder progress.Logical formLearned from9 sentences. An (obstacle course) can be underwater.Logical formLearned from9 sentences. Obstacles may be impeded.Logical formLearned from9 sentences. Contact can be with obstacles.Logical formLearned from9 sentences. Obstacles can be topographic.Logical formLearned from9 sentences. Obstacles can be on some sides.Logical formLearned from9 sentences. Obstacles can be to research.Logical formLearned from9 sentences. Obstacles can be to sustainable development.Logical formLearned from9 sentences. A female may overcome some obstacles.Logical formLearned from9 sentences. An obstacle can be circular.Logical formLearned from9 sentences. An obstacle can be terrible.Logical formLearned from9 sentences. An obstacle can be a tendency.Logical formLearned from9 sentences. An obstacle can be unreasonable.Logical formLearned from9 sentences.