Relative clauses are types of dependent clauses complete independent sentences - they usually refer to a single word and modify them. Here, in this excerpt, the relative clause would be that we can see in nature. Relative clauses usually begin with pronouns such as who, what, that, etc.
A. You will want to make a plan and prepare your outline in order to formulate what your paper will say. This can also help you determine if you have enough info to write your paper
Everyone 
done his or her homework.
Explanation:
Everyone is singular and, therefore, require singular verb.
Answer:
Oreki and Chitanda from Hyouka
