1. I will break the window. [Will is stressed.]
2. I will break the window. [Will is not stressed.]
3. I'll break the window.
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#1 shows that the subject has a strong will.
What about #2? When 'will' is not stressed, does it mean the volition of the subject, which is a little weaker than #1? Or does it mean the simple future?
#3 means the volition of the subject, but it is weaker than as in #1. Am I right?
You're right about #1.
The simple future tense is all that's meant in #2 and #3 without stressing any particular syllable or word.
(Haven't we been through this before?)