What was the theme of Mr Dexters Dragon

Which punctuation mark would best fill in the blanks in the following sentence in the past year i visited denver, colorado portland oregon and seattle washington

Karen often finds that tasks come up unexpectedly during her day, and she has trouble figuring out how to rearrange her schedule because she changes it daily.  what should karen do to prevent these unexpected tasks from disrupting her day

In this unit we learned about arguments and rhetoric. in an argument we use ,not informal language