They are both like each other because they are both in very unhappy marriages.
Um...Your right you want to rekonsider geting a snake,they are really,really,REALLY not 'harmless',and sorry that I may not have answer your question the right way,but I tried!
Theme means the subject of a piece of writing or a play or etc.
here are some examples of theme in a sentence.
1) The theme of the play was that true friendship is hard to found.
2) He decided to write a story with a different theme from his other works.
3) I decided the theme of passage I have read was a good life lesson.
Hope this helps! :)
Maybe you can create some sentences of your own! :)