I ordered a blue notebook.
Just because it's the same sentence doesn't mean it should always be said the same way. In English, which word you make stand out isn't decided within the sentence alone. The answer changes depending on what the other person said just before. Put this one sentence into three situations, and that becomes clear.
When you're correcting the colour
A: You ordered a red notebook, didn't you?
B: No, I ordered a blue notebook.
A is assuming it was a red notebook. That a notebook was ordered is correct; only the colour is off. So what B stresses is blue. Notebook is a word A has already said, and it's already shared between the two of them. There's no reason to say it forcefully. Put into English, it would be “No, a blue notebook” — the way the force lands is exactly the same.
When you're correcting the item
A: You ordered a blue pen, didn't you?
B: No, I ordered a blue notebook.
This time the colour is right and the item is different. The only point to make is “Not a pen — a notebook,” so the stress shifts to notebook. Blue is just as A said. If you stressed blue as well here, the listener wouldn't know what the difference is.
When you're asked the colour
A: What colour notebook did you order?
B: I ordered a blue notebook.
Here, nobody has got anything wrong. A knows a notebook was ordered; the only thing A doesn't know is the colour. Blue, which fills that blank, naturally stands out as new information. Even with zero correction, the place of the stress is still clearly decided.
Side by side, there's just one rule
A's previous utterance | What is already shared | What the reply newly puts forward | The word that stands out
red notebook? | That a notebook was ordered | Correcting the colour from red to blue | blue
blue pen? | That something blue was ordered | Correcting the item from pen to notebook | notebook
What colour notebook? | That a notebook was ordered | Answering the colour asked about | blue
As you can see, blue stands out both when you're correcting the colour and when you're answering about the colour. What decides it isn't “whether it's a correction or not.” It's what, in relation to the previous utterance, the reply newly puts forward and what it replaces. That's all.
It doesn't have to end as a matter of feel. The British Council's pages for teachers also explain properly how the meaning conveyed changes with the position of stress, and line up four recordings of the same English sentence with the stress placed in different spots (TeachingEnglish's explanation of sentence stress). Listen and compare, and your ears will be convinced before the theory.
To check whether it landed, have the listener guess
Just because you meant to stress a word doesn't mean it reached the other person. The check is simple, and the fastest way is to have the listener guess.
- Choose one of the three exchanges and, without telling the other person which, say B's reply
- Ask the other person, “Which word sounded most prominent to you?”
- If the answer differs from your intention, look back at how you said the word you meant to make stand out
What to aim for isn't a loud voice. It's sounding more prominent than the rest. If blue and notebook are both equally strong, the focus blurs and the listener can't judge. If there's no partner, a recording will do. Leave some time, then listen back without looking at A's lines.
There's a reason the question to ask is not “what did I correct?” but “which word stood out?” A reply correcting the colour and a reply answering the colour cannot be distinguished by stress alone. What you're having them guess isn't your intention, but strictly how it sounded.
Even when you're the listener, the answer is in what was said before
In a conversation, if blue sounds especially prominent, you can make a guess: “The colour is the focus of this reply.” But whether that's a correction or an answer to a question about colour — and, if it's a correction, what colour was mentioned before — cannot be decided by stress alone. The only way is to listen to the utterance just before and check.
Whether you're speaking or listening, stress is something you read together with the previous utterance as a set. If you add your own rows to the table above, swapping in different colours and items, you can test this judgement as many times as you like. If you're unsure about how to choose the material itself for practice, the published Five perspectives for looking at practice material is also worth reading alongside. Once the material is decided, all that's left is to listen to what was said before and decide which word to stress. Repeat that.