Final answer:
The sentence is a simile because it uses "like" to compare the woman to a sack of potatoes.
Step-by-step explanation:
The sentence "The tired woman fell into bed like a sack of potatoes" is a simile because it uses the word "like" to compare two things. A simile is a figure of speech that compares two things using the words "like" or "as." In this case, the tired woman is being compared to a sack of potatoes to convey how she fell into bed in a similar manner, emphasizing her fatigue and lack of energy.
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