Scientists may study effects of pollution.Logical formLearned from4 sentences. Changes may allow (air pollution).Logical formLearned from4 sentences. Cities can be with (air pollution problems).Logical formLearned from4 sentences. Pollution may be addrest.Logical formLearned from4 sentences. Pollution can be from landfills.Logical formLearned from4 sentences. Pollution can be magical.Logical formLearned from4 sentences. Marine pollution may undergo a reduction.Logical formLearned from4 sentences. Investigations can be into environmental pollution.Logical formLearned from4 sentences. A complaint can be about an (air pollution problem).Logical formLearned from4 sentences. (Air pollution) can be from some coal-fired (power plants).Logical formLearned from4 sentences. (Pollution sources) can be subject to (pollution controls).Logical formLearned from4 sentences. A matter may control pollution.Logical formLearned from4 sentences. (Pollution levels) may undergo a reduction.Logical formLearned from4 sentences. Emphasis can be on (air pollution).Logical formLearned from4 sentences. A concern can be for pollution.Logical formLearned from4 sentences.