WHAT IS AN UNWRITTEN RULE ABOUT SCHOOL, THAT EVERYONE STILL SEEMS TO KNOW?

If there is ever a school project, look at your friend and nod and if they nod back, you two are partners.

ha hew jsk whne hsk huaob hdjok bshe hew hau ? ?

explanation:

quite an interesting way to teach topic sentences, because the answer to this question is the best definition of a topic sentence that one can present, it is as if answering the questions taught you how to do it, this is some real teaching, it is terribly well-done.

the topic sentence in this paragraph is:

topic sentences writers stay on track and keep a paragraph from becoming an aimless collection of sentences about an idea.

which incidentally tells you what a topic sentence should be.