In order to do this, you must spend some time doing preliminary background research so that you are able to write convincingly of your topic's positive contribution.
Try to avoid statements such as:
"Please give me this topic because I want it."
"Please give me this topic because I like it."
~refer to the next blog post about tips for persuasive writing for more help.
(remember that a paragraph is usually 6-8 sentences)
1st paragraph: Introduction to your topic.
2nd paragraph: Why your topic is an important topic to study (introduce your evidence to support your argument)
3rd paragraph: Introduce what you know about the positive contribution of your topic to the service of humanity.
4th paragraph: Why this topic is meaningful to you. Why did you select this topic?
5th paragrpah: Conclusion to your topic and of your argument.