The rhythm of Iambic pentameter is: da DA da DA da DA da DA da DA; note that this is 10 syllables in the line. Another example is the familiar "the mouse ran up the clock" line: the ^mouse ran ^up the ^clock, the ^clock struck ^one; again you have 10 syllables in the line. Note that even though all the words in this line are single-syllabled, there is only one way you can stress it.
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