Swimming is an action verb because you can do it. Fast is not an action verb it is an adjective.
A hungry wolf shouted at his pack.
A comfortable couch sat in the lounge, waiting to be accompanied.
A car ran down the highway.
A cell phone sang its ringtone.
A butterfly danced through the air.
A dinosaur settled down to rest.
Stars beamed the night sky, looking down on the earth.
Mountains sat omnipotently, watching over the surrounding villages.
Ocean waves ran along the shoreline.
A boiling pot sighed steam out once the lid was opened.
The answer is: [D]:
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They are often used to combine choppy sentences.
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Conjunctions are often used to combine choppy sentences.
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Note: The questions asks about CONJUNCTIONS —NOT about "contractions".
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Choice "A" is incorrect. They are not used to combine two or more LONG sentences. If sentences are already long, then do not need to be combined with a conjunction.
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Choice: "B" is incorrect. To the contrary, the use of conjunctions actually makes sentences longer.
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Choice "C" is incorrect. To the contrary, the use of conjunctions should be used (appropriately, of course) in essays. The use of "contractions" should not be used in essays or formal writing.
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Choice "D" is correct. They are often used to combine choppy sentences for better reading and engagement.
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