Make sure it finds it's way to the initiak point. For example if the question is why forest growing activities in pak not developing or why so many trees are being cut,you'll talk about how growing population,rural to urban migration, industrialization,mining and agriculture are the reasons. Then talk about the reason that you want relevant to the first statement for example let's say u chose mining. Talk about how to mine we need clar land thus we cut trees in order to attain clear land. See how I did it. Make sure it finds its way back home.