Jack Kerouac’s narrative On the Road displays not just one style but various styles of writing, and it is partly this stylistic diversity that gives the book much of its interest and appeal.
Sometimes, for example, the style is simple and plain, showing some of the influence of the no-nonsense phrasing associated with Hemingway:
I first met Dean not long after my wife and I split up.
Sometimes the phrasing is suggestive and tantalizing, reminiscent in some ways of the phrasing we associate with Holden Caulfield in The Catcher in the Rye:
I had just gotten over a serious illness that I won't bother to talk about . . . .
Sometimes the phrasing manages to seem colloquial and “literary” at the same time:
. . . he was a young jailkid shrouded in mystery.
Sometimes the phrasing uses vivid slang:
Dean was staying in a cold-water pad . . . .
On other occasions it piles on adjectives:
. . . his beautiful little sharp chick Marylou . . . .
At other times the details are precise and almost sensual:
. . . beautiful big glazed cakes and creampuffs . . . .
Quoted speech is often used, and usually that speech is credibly colloquial:
All this time Dean was telling Marylou things like this: "Now, darling, here we are in New York and although I haven't quite told you everything that I was thinking about when we crossed Missouri and especially at the point when we passed the Booneville reformatory which reminded me of my jail problem, it is absolutely necessary now to postpone all those leftover things concerning our personal lovethings and at once begin thinking of specific worklife plans . . ."
All the details just quoted show the range and variety of Kerouac’s style, which are also visible here:
My first impression of Dean was of a young Gene Autry-trim, thin-hipped, blue-eyed, with a real Oklahoma accent-a sideburned hero of the snowy West. In fact he'd just been working on a ranch, Ed Wall's in Colorado, before marrying Marylou and coming East. Marylou was a pretty blonde with immense ringlets of hair like a sea of golden tresses; she sat there on the edge of the couch with her hands hanging in her lap and her smoky blue country eyes fixed in a wide stare because she was in an evil gray New York pad that she'd heard about back West, and waiting like a longbodied emaciated Modigliani surrealist woman in a serious room.
Note the reference to popular culture (Gene Autry was a film star), the series of vivid adjectives, the precision of the reference to Dean’s accent, and the wonderfully striking description of dean as “a sideburned hero of the snowy West,” which makes him sound almost mythic even as it implies the imaginative qualities of the narrator’s own mind. The reference to “Ed Wall’s” ranch makes the account seem grounded in very specific facts, and while the initial description of Marylou is more conventional and stereotyped than the description of Dean, it at least tries to be vivid. Far more genuinely vivid (because less predictable) is the ensuing description of Marylou, especially the phrasing that begins with “longbodied,” which implies the narrator’s cultural sophistication and his efforts to be as precise as possible.
In short, Kerouac’s style is neither monotonous nor predictable; he uses words with care and creativity, shifting from one kind of phrasing to another whenever he needs to do so.