An obstacle can be unavoidable.Logical formLearned from14 sentences. An obstacle can be a refusal.Logical formLearned from14 sentences. An obstacle can be in a campaign.Logical formLearned from14 sentences. Obstacles can be to understanding.Logical formLearned from14 sentences. An obstacle can be institutional.Logical formLearned from14 sentences. An obstacle can be to happiness.Logical formLearned from14 sentences. Obstacles can be inconvenient.Logical formLearned from14 sentences. An obstacle can be to a relationship.Logical formLearned from14 sentences. An obstacle can be to integration.Logical formLearned from14 sentences. (Relief teams) may grapple with obstacles.Logical formLearned from14 sentences. An obstacle can be to a ratification of a treaty.Logical formLearned from14 sentences. An obstacle can be financial.Logical formLearned from14 sentences. A number of obstacles may increase.Logical formLearned from14 sentences. An election may remove an obstacle to a takeover of government.Logical formLearned from14 sentences. Costs can be an obstacle.Logical formLearned from14 sentences.