Saying "dunno" instead of "don't know" is an error in

How does gatsby smile at nick? why is this important?

How did sundara learn to speak english

When first i engaged in this work, i resolved to leave neither words nor things unexamined, and myself with a prospect of the hours which i should revel away in feasts of literature . . –preface to a dictionary of the english language, samuel johnson what is the connotation of the word revel in this passage?