Answer:
There are four prepositional phrases in the sentence given.
1. at the bottom of the steps 2. with a smile 3. of ineffable joy 4. attitude of matchless grace and dignity.
<u>Explanation:
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<em>A prepositional phrase is a phrase consists of preposition and its object.</em>
The first phrase is ‘<em>at the bottom of the steps’</em>, where the<em> preposition of place, ‘at’, is used to refer to the object of the steps.
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The second phrase is ‘<em>with a smile</em>’, where <em>‘with’ is the preposition of instrument, and it is used to refer to the object, smile.
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The third phase is ‘<em>of ineffable joy</em>’ which refers <em>to its object, describing the joy held by the author.
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The final phrase is <em>‘attitude of matchless grace and dignity</em>', <em>where of preposition is used again to describe the quality of the girl.
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