Does anyone know how to do internal citation in mla format

In the story, juvencio states that he had to kill don lupe. what does this line reveal about how he views his deed? (tell them not to kill me)

Read the passage: canines may not be the deepest thinkers in the world. but perhaps that's for the best. the life of a dog—sitting alone all day, waiting for everyone to come home—can be pretty boring. super-smart animals would probably get totally stressed out, says university of pennsylvania researcher james serpell. look at it this way: if dogs were any smarter, they probably wouldn't choose to hang around with us. which best describes the tone of the passage?

What do u think u might go with a bestfriend that u don’t do with everyday friends( school friends)