A (coal output) may pertain-to a country.Logical formLearned from106 sentences. Coal may be produced.Logical formLearned from106 sentences. An explosion may rip through a (coal mine).Logical formLearned from106 sentences. A coal may be mined.Logical formLearned from105 sentences. Clean coal can be from a us-state.Logical formLearned from103 sentences. A coal can be liquefied.Logical formLearned from100 sentences. (Coal miners) may pertain-to a country.Logical formLearned from100 sentences. A (coal mine) can be abandoned.Logical formLearned from99 sentences. A (coal industry) may pertain-to a country.Logical formLearned from99 sentences. A (coal miner) may pertain-to a us-state.Logical formLearned from99 sentences. A coal may pertain-to a male.Logical formLearned from98 sentences. A (coal company) may pertain-to a country.Logical formLearned from97 sentences. Some (coal miners) may be trapped.Logical formLearned from97 sentences. Accidents can be common in a (coal industry).Logical formLearned from97 sentences. A (coal mine) can be in a province.Logical formLearned from96 sentences.