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

GRAMMATICALLY CORRECT
He knew she'd never ask him for a loan.
[Other people thought she would.]
He knew she'd never ask him for a loan.
[He had good reason to know she wouldn't.]
He knew she'd never ask him for a loan.
[Someone else would be asking him for one.]
He knew she'd never ask him for a loan.
[She wouldn't do so in a million years.]
He knew she'd never ask him for a loan.
[She might hint strongly, though.]
He knew she'd never ask him for a loan.
[She might ask someone else.]
He knew she'd never ask him fora loan.
[She'd be more likely to offer him one.]
He knew she'd never ask him for a loan.
[She wouldn't stop at just one.]
He knew she'd never ask him for a loan.
[She'd prefer an outright gift.]
As effective as italic type can be, do not rely on it excessively as
a means of injecting excitement or importance. Good writers achieve
emphasis through wording and punctuation, not through typographical
tricks. Mostly, you should reserve italics for cases where the
intended meaning would not be clear without them, or where you
feel that a desired emphasis could not be made apparent through
wording alone.
EMPHASIZING A SPEAKER'S WORDS
In dialogue, italics are often used to indicate words that a speaker
is stressing, saying loudly or saying with particular significance. (This
device should be reserved for fiction. It is usually not appropriate
to include italics when quoting a real person's speech in a report or
article.)
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