|
Yesterday,we didnt have cars.But today we have.Yesterday,we didnt have TV sets.But today we have.Yesterday we didnt have computers.But today we have.During the hundreds of years,how fast the world has changed!Thats really a myth. Though the new world brings us a convenient life.It also brings more problems.For example,population,resources ,environment and so on. We know that the worlds population is growing faster and faster. Its more than 6 billion now.Its a very big number.We can say the number of worlds population is like the number of the stars in the universe.And if it goes on like that,I cant image what will happen. As the second problem,the world is short of resources now.In daily life,we need water,rock oil,coal and other things.Day after day,the resources disappear fast.And they wont appear.Because most of them are not renewable resources. The third problem is environment.Everyone talks about it.The weather is hotter and hotter .That means we pollute the environment seriously.Our cars make the air dirty.Old batteries make the soil poisonous.Waste water makes clean water dirty.So we dont have fresh air,fecund soil and pure water.Oh,no.Stop polluting! Now we human beings should face the new challenge .We must think more about our mother earth.Remember:We dont have another earth! | 
