A poem has a rhyme scheme when its words rhyme in a regular pattern. Words normally rhyme at the end of each line, or at the end of every other line. These are printing terms that describe two styles of font or typeface. We are shaped by the society and the times in which we live. You are expected to know when and how your set-text authors lived, and to make comments about how this might have affected what they wrote.
Speculation is an informed guess about something.
Our advice is simply avoid slang in formal situations. These are questions that are in several parts. The syntax of a sentence is the grammatical structure of a sentence. A testimony is a long, formal statement made with the intention of proving something. A text is anything written.