纵横四海2000
With the more and more densely populated world, air pollution has become a serious problem. Air pollution mainly comes from four areas of human activities: industry, energy, transportation and agriculture. Running factories, providing power for trains, planes and buses all need energy. Almost all of the energy is produced by burning fuel, which leads to air pollution. Scientists are studying new ways of electricity generation to reduce environmental damage. also with the enhancement of public environmental awareness such as recycling.
panda熊猫陈
您好，很高兴为您解答：As the world's population increases(densely populated), air polution had became a serious problem. Air polution mainly comes from four main category: building industry, energy industry, traffic transportation and farming. We need power source to run factories, trains, airplanes, and buses. (But) Almost all the power source comes from fuel combustion, and this will cause air polution. Scientist are trying to find a way to create power source, but create less harm to the enviroment. 最后一句不大懂。国外上学，作业没写完，纯手码，一定要采纳啊！谢谢了。
加油嘴馋的我
he learned how to speak English in 6 months.whatever you say, I will stick to my plan.we will set out as soon as the rain stops.she's been writting letters since 4 o'clock in the afternoon.he's planning to go to Guilin in Summer holiday.people will not know the value of health until they lose it.don't believe him, no matter what he says.he cannot stay here. he must leave right away.
未央1895
As the world population is becoming more and more densely populated (densely populated),air pollution has become a serious problem. Air pollution comes mainly from four main areas of human activities: industry, energy industry, transportation industry, and agriculture. Operations of factories providing power for trains, airplanes and buses all require energy. Almost all of this energy is produced through burning fuel and this will result in air pollution. Scientists are researching new methods of electric power generation that can reduce environmental damage. Enhanced public environmental awareness causes activities such as recycling (recycling) and other activities to come into being.如果答案对亲有所帮助请采纳予以鼓励!如果有疑问欢迎追问...
如此娇弱
1．他在六个月之内学会了说英语。He learned to speak English within six months. 2.不管你说什么，我都会坚持我的计划。No matter what you say, I will stick to my plan. 3．雨一停，我们就动身。When rain stops, we'll leave. 4．从下午四点钟到现在，她一直在写信。From four o'clock till now, she has been writing the letter. 5．他打算暑假时去桂林。He plans to visit Guilin in the summer holiday. 6．人们直到失去了健康，才知道健康的可贵。Until people lost their health, then they know the valuable of health. 7．无论他说什么，都别相信他。No matter what he says, don't trust him. 8、他不可以在这儿待下去，他得马上离开了。He can't be to stay here, he had to leave immediately.
