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

GRAMMATICALLY CORRECT
capitalized if it seems appropriate. See the discussion under "Capitalization"
on page 269.)
Mrs Palmer's eye was now caught by the drawings which hung
round the room. She got up to examine them.
'Oh! dear, how beautiful these are! Well! how delightful! Do but
look, mama, how sweet! I declare they are quite charming; I could
look at them for ever.' And then sitting down again, she very soon
forgot that there were any such things in the room.
-jANE AusTEN, Sense and Sensibility
I took the subway to group ... and tried to concentrate on how
I was going to tell the group what had happened to me. I felt mortified.
Two years earlier, I had walked off into the sunset-cured! it's a miracle!
she can walk!-and now I was back again, a hopeless cripple.
-NoRA EPHRON, Heartburn
An exclamation of horror broke from the painter's lips as he saw
in the dim light the hideous face on the canvas grinning at him.
There was something in its expression that filled him with disgust and
loathing. Good heavens! it was Dorian Gray's own face that he was
looking at!
-OscAR WILDE, The Picture of Dorian Gray
INDICATING RHETORICAL QUESTIONS
It is sometimes appropriate to end a rhetorical question-one for
which no answer is expected-in an exclamation point instead of a
question mark.
How do you expect me to finish all these chores by noon!
Isn't he adorable!
What on earth did she expect!
See also the examples of rhetorical questions under "Question
Mark" on page 117.
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