What evidence should be added to the simple paragraph to support the reason ?

Evidence. This is how you support, or back up, your claims. The evidence will help to "prove" each claim to the reader. In a paper that incorporates research from secondary sources, your evidence may include information from articles, books, electronic sources, or any of the research you gathered.

Extra evidence can generally be added to support a reason, but it would be more helpful if I actually knew what paragraph you're talking about

a conclusion based on evidence is an example of a. inference