Final answer:
The colon is used incorrectly in the sentence. It should be replaced with a comma to separate the items in the list.
Step-by-step explanation:
The colon is used incorrectly in the sentence: 'We drank: smoothies, milkshakes, and soda.' A colon is used to introduce a list, explanation, or quotation, but it should not be used before a list that follows a verb. In this case, the colon should be replaced with a comma, as in 'We drank smoothies, milkshakes, and soda.'
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