英语主语从句句子编写有关减轻、消除雾霾的建议,要求至少出现两个主语从句,不少于50字!

What causes the smog is not yet fully understood,but there's still some initiatives to alleviate the smog problem.Reducing automobile waste production is one of them.Considering the particles that form smogs come partly from automobile waste,to reduce the waste is definitely reducing smog.The ways that we can reduce automobile waste are plenty,such as implementing higher standard of petrol,etc.