Locate the complete infinitive phrase and identify its use. to play the piano was melanie's dream.

The correct answer is: "To play the piano" . Here is used as a noun.

Explanation:

Infinitive phrases are those phrases that begin, as the name implies, with an infinitive (to + verb in the simple form).

As we can see in this case: "To play the piano".

The function of the infinitive phrases can be: adjectives, nouns or adverbs.

As a noun, its function is like the subject of the sentence.

d) the narrator even suggested that the white whale, moby d, was ubiquitous and present in every ocean at every moment.  

chapter i -- paris: september, 1792

a surging, seething, murmuring crowd of beings that are human only in name, for to the eye and ear they seem naught but savage creatures, animated by vile passions and by the lust of vengeance and of hate.

during the greater part of the day the guillotine had been kept busy at its ghastly work: all that france had boasted of in the past centuries, of ancient names, and blue blood, had paid toll to her desire for liberty and for fraternity.

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