Grammatically Correct: The writer's essential guide to punctuation ...

Ann's Conscience, which up till this morning had been standing
STYLE
aside and holding a sort of watching brief, now intruded itself upon
the scene.
'I don't want you to think I am always shoving myself forward,'
said Conscience frigidly, 'but I should be failing in my duty if I did not
point out that you are standing at a Girl's Cross Roads. Everything
depends on what reply you make to the very leading question which
has just been put to you .... whatever you do, let me urge upon you
with all the emphasis of which I am capable not to drop your eyes
and say "Yes." '
'Yes,' said Ann, dropping her eyes. 'Of course I did.'
-P.G. WooEHousE, Big Money
Our chairs were adjoining, and when Mario had finished with me
and was ready to take off and shake out that cloth throwover, I never,
never failed to have more of Seymour's hair on me than my own. Only
once did I put in a complaint about it, and that was a colossal mistake.
I said something, in a distinctly ratty tone of voice, about his "damn
hair" always jumping all over me. The instant I said it I was sorry, but
it was out. He didn't say anything, but he immediately started to worry
about it. It grew worse as we walked home, crossing streets in silence;
he was obviously trying to divine a way of forbidding his hair to jump
on his brother in the barbershop. The homestretch on 11 Oth, the long
block from Broadway to our building, on the corner of Riverside, was
the worst. No one in the family could worry his or her way down that
block the way Seymour could if he had Decent Material.
-J.D. SALINGER, Seymour: An Introduction
In dialogue, whole words or sentences may sometimes be capitalized
in order to indicate shouting or vehemence.
Alice laid her hand upon his arm, and said, in a soothing tone, 'You
needn't be so angry about an old rattle.'
'But it isn't old!' Tweedledum cried, in a greater fury than ever. 'It's
new, I tell you-1 bought it yesterday-my nice NEW RADLE!' and his
voice rose to a perfect scream.
-LEWIS CARROLL, Through the Looking-Glass
267