Page 197 - Practical English Usage 3ed - Michael Swan, Oxford

Or we may wish to show a contrast between, for example, true and false, or present and past, or a rule and an exception ('contrastive emphasis').
Why weren't you at the meeting?-I was at the meeting.
I don't do much sport now, but I did play football when I was younger. I don't see my family much, but I do visit my mother occasionally.
We can also use emphasis to show that something expected actually happened.
I thought I'd pass the exam, and I did pass.
2 pronunciation: stress
In speech, we can give words extra stress - make them sound 'stronger' - by pronouncing them louder and with a higher intonation (see 554). We may also make the vowel longer, and pause before a stressed word. Stress is reflected in printing by using italics or bold type, and in writing by using CAPITAL LEITERS or by underlining.
This is the last opportunity.
He lived in France, not Spain.
Mary, I'm IN LOVE! Please don't tell anybody!
Changes in stress can affect the meaning of a sentence. Compare: Jane phoned me yesterday. (Not somebody else.) . Jane phoned me yesterday. (She didn't come to see me.)
Jane phoned me yesterday. (She didn't phone you.)
Jane phoned me yesterday. (Not today.)
We often stress auxiliary verbs. This can make the whole sentence sound more emphatic, or can emphasise a contrast (see above). Most auxiliary verbs change their pronunciation when they are stressed (see 616).
You have grown!
I am telling the truth - you must believe me!
In emphatic sentences without auxiliary verbs we add do to carry stress.
Do sit down. She does like you.
If he does decide to come, let me know, will you?
With stressed auxiliary verbs, word order can change (see 24.9). Compare:
You have certainly grown. You certainly have grown!
3 vocabulary: special words
Words such as so, such, really and just can show emphasis.
Thank you so much. It was such a lovely party. I really enjoyed it. I just LOVE the way she talks. (Note: love is stressed, not just.)
Swearwords (see 575) are often used for emphasis in an informal style.
That's a bloody good idea.
Question words can be emphasised by adding ever (see 624), on earth or the hell (very informal).
Why ever did he marry her?
What on earth is she doing here? Where the hell have you been?
4 structures
If we can move words to an unusual position, this usually gives them more importance. Words are often 'fronted' for this reason (see 513).
That film - what did you think of it? Asleep, then, were you?
I knew he was going to cause trouble, and cause trouble he did! •
emphasis 184
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