What part of her body does Julia have in a sling?
You can find the answer to the question in the first few sentences of Chapter 9. What Julia has in a sling is her right arm.
This is before she and Winston have started her affair. Winston thinks that she has probably hurt her arm while working with some of the machinery that is used in her department. As it turns out, she is going to use the sling as a way to make contact with Winston. She falls down right in front of him and when he helps her up, she slips him a note saying "I Love You."
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