The website "Teaching English" has a few articles about English intonation and rhythm (and proncunciation in general). Lynn Gallacher's article English sentence stress describes a few exercises:
- Using limericks and other forms of poetry, since stress timing is very noticeable in this type of language. Students can even read their own limericks and read them out, trying to keep the rhythm.
- Use a recording of a dialogue, e.g. from a course book: listen to it, then record yourself speaking the dialogue again and again until it sounds as close as possible to the recording.
Steve Darn's article Rhythm lists a number of teaching techniques but does not elaborate on them.
(Marta J. Sabbadini's article Intonation also contains a few suggestions, e.g. on how intonation is used in a dialogue to distinguish between "new" information and "shared knowledge".)
Sarah Tolle's blog post Feel the Rhythm of English and Improve Your Pronunciation! on the Fluent U blog explains what a stress-timed language is and describes three pronunciation exercises to improve your rhythm in English:
- "Echo activity": first read a word with a stressed syllable (emphasizing the stressed syllable as much as posible), then read a short sentence that has a similar stress pattern.
- "Movement activity": add a movement such as clapping your hands to emphasize the stressed parts in a sentence.
- "Bouncing ball activity": use a bouncing ball to guide your stress-timing; you'll need to find a steady pattern, without speeding up or slowing down the dribbling.
Maria-Josep Solé Sabater's paper Stress and Rhythm in English contains a long discussion of stress and stress-timed rhythm, and present some material for practising English stress and rhythm, for example:
- Practising phrases that have the same stress pattern as single words (see the "echo activity" in Sarah Tolle's blog post).
- Finding phrases that have the same stress pattern the words listed in that section of the paper.
- Finding phrases or sentences with the same distribution of stresses as the list provided in the paper.
- Practising unstressing in function words.
- Practising isochronicity of English rhythm by snapping your fingers or tapping your foot at a regular rhythm while pronouncing sentences.
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For more tips, see Claudia Pesce's article 7 Excellent Exercises to Improve ESL Intonation and Stress.