Answer:
The dog jumped [on] the sofa.
In this sentence, the correct preposition to use is "on." We use the preposition "on" when we want to indicate that something is physically positioned above or touching a surface. In this case, the dog is physically positioned above the sofa and touching it, so we say "on the sofa."
Using the preposition "in" would imply that the dog is physically inside the sofa, which is not the intended meaning in this sentence.
Step-by-step explanation:
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