I believe the answer is "Begin sentences with different parts of speech"
Hello. You have not informed which novel you are referring to, which makes it impossible to answer your question satisfactorily. But I can help you by showing you how to identify a primary source in this novel.
A primary source is a document that depicts a historic event. This document was built at the time that this historic event took place, being built without the interference and influence of other sources, being, therefore, a primary source. This type of document must be exposed in the novel related to your question.
An example of this would be a novel that featured a character who wrote a diary about his experiences during the discovery of gold in Georgia. In that case, the diary would be a primary source.
Used for a small pause, lists , letters