Subscribe to The Chicago Manual of Style Online
Usage and Grammar
Q. Hello. Is it appropriate to use ’s for “is”? For example: John’s running every day.
A. It’s a little informal for expository prose, where it would be better to write “John is running every day.” But in quoted speech or dialogue in a story or a novel, the contraction might be the best choice for representing how the sentence was actually spoken or how it might be spoken in real life. In sum, Chicago’s not going to tell you that you can’t use it. Ba dum tss.