'Do You Not Know' in the Bible

Or, do you not know that all of us who were immersed into Christ Jesus were immersed into His death?

Do you not know that you are the slaves of whoever you offer your obedience to? If you obey [the desire to] sin, it leads to [spiritual] death; or if you obey [God] it leads to righteousness.

Or, do you not know, brothers, (I am talking to people who know how law works) that the law has authority over a person only as long as he lives? [Note: It is not clear whether this refers to Roman law or the law of Moses].

God did not reject His people whom He knew previously. Or, do you not know what the Scriptures say in the passage where Elijah pleads with God against Israel?