What is word stress in English, and how can shifting stress change a word's meaning?

In one line

Word stress is the extra force, length and pitch given to one syllable of a word, and in some words moving the stress changes the meaning or word class.

Explained simply

Say 'baNAna'. Now say 'BAnana'. The second sounds odd, though the letters are the same. Every English word with two or more syllables has one syllable that is said louder and longer. Getting it wrong can make a correct word sound unfamiliar.

Technically, a stressed syllable is louder, longer and higher in pitch than the others. Dictionaries mark it with a stress mark (ˈ) before the syllable. Word stress is part of the pronunciation, stress and rhythm component of the MU speaking module.

How it works

1. Count syllables: com-pu-ter (3).
2. Find the stressed one: comPUter, PHOtograph, phoTOgraphy, photoGRAPHic. Stress can move within a word family.
3. Two-syllable noun/verb pairs: nouns and adjectives usually stress the first syllable, verbs the second.

4. Word	Noun (first syllable)	Verb (second syllable)
   record	REcord (a written account)	reCORD (to note down)
   present	PREsent (a gift)	preSENT (to show)
   object	OBject (a thing)	obJECT (to oppose)
   conduct	CONduct (behaviour)	conDUCT (to carry out)

5. Common suffix patterns: words ending in -tion, -sion and -ic stress the syllable just before the ending (inforMAtion, deCIsion, elecTRONic).
6. Check any doubtful word in a dictionary.

Quick example

A presenter says 'We will reCORD the readings and then PREsent the results.' Listeners pause: 'PREsent' sounds like a noun (a gift). The correct verb form is 'preSENT the results'. In engineering speech, also note deVElop, deVElopment, and ENgine but engiNEER.

Common mistakes

• Stressing every syllable equally, a common Indian English pattern that reduces clarity.
• Using the noun stress for the verb in pairs like record, present, object.
• Assuming stress always falls on the first syllable.

How MU asks it

Asked in theory as 'What is word stress? Explain with examples' (3 marks), or 'Mark the stress in the following words' (short items), and within pronunciation questions (5 marks). Define stress, explain loudness, length and pitch, give noun-verb pairs, and show stress shift in a word family.