Which sentence is punctuated correctly

The truth question is

What is the sentence?

- "the basic difference between keywords and subjects is that subjects (or "subject headings") have been predetermined, while keywords have not. a keyword is an easy place to start because you can use any word that seems to fit your search; this is called "natural language" searching."

a personal narrative essay is about a personal experience, so it is usually written in the first person. to maximize its impact, the essay should: be written to have an emotional impact on the reader. include a lot of references to sensory perceptions and hope i