The problem with cutting down trees is that it destroys some animals' habitats and it also destroys the oxygen we breath. A good thing about cutting down trees is that the lumber industry makes a good profit and having less trees creates more space.
A bad thing about building highways is that it takes up a lot of useful land and also costs a lot to create. A good thing about building highways is that it is very useful for transportation.
The problem with building houses is that they take up space and cost a lot of money to build. A good thing about building houses is that it provides a home for families and that they last a long time.
A solution to saving land would be to have a variety of different apartments and houses. Also, limiting the amount of land each house gets would be a good way to save land for the future.
A good thing about building factories is that factories provide many different supplies that are useful. A bad thing about factories is that factory smoke can pollute our air and emit chemicals that can hurt our ozone layer.
A good thing about hydroelectric power dams is that they provide electricity from water. A bad thing about hydroelectric power dams is that they are very expensive, take up space, and can disturb animals in the river.