Final answer:
A phrase that ends in -ing and acts as a noun is known as a gerund phrase. For instance, in the sentence 'Swimming is my favorite sport', 'Swimming' is a gerund that functions as a noun.
Step-by-step explanation:
A phrase that ends in -ing and functions as a noun is known as a gerund phrase. An example of a gerund phrase could be 'Swimming is my favorite sport.' Here, 'Swimming' functions as a noun, as it is the subject of the sentence and refers to the activity of swimming. Gerund phrases are useful in sentence construction because they allow for more complex ideas to be expressed concisely.
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