sentences: shade oil is a sink of land purity & rest oil requires shade oil ->  using coal is a source of air pollution  using coal is a source of air pollution & purity has a yes clip on the ml / land good / land good / tornadoes ->  using coal has a negative impact on an ecosystem  using coal has a negative impact on an ecosystem & a solution has a impossibility yes stay on a place ->  a problem with using coal is that it has a negative impact on an ecosystem  a problem with using coal is that it has a negative impact on an ecosystem & repair has a yes feathers on a place -> a problem with using coal is that it damages an ecosystem