The metrical "feet" in the classical languages were based on the length of time taken to pronounce each syllable. A dactylic foot consists of a long syllable followed by two short syllables. A spondee consists of two long syllables. A trochee consists of a long syllable followed by a short one. The "foot" is often compared to a musical measure and the long and short syllables to whole notes and half notes.
Accordingly, a line of dactylic hexameter can be diagrammed as follows. Note that - is a long syllable, u a short syllable, and U either one long or two shorts:
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