You will notice that on a US keyboard, shift-4 is "$", which is the bash variable expansion character.

注意到了吗：在美国键盘上，shift-4 是 "$"，它是 bash 变量扩展字符。

youdao

He was angry because he had to run FiOS up from the basement and his shift ended at 4.

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She also asked her mother to wash her uniform so she could work the 4 p.m. shift at Popeye's Chicken.

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To pay the fees, she worked at a call center on the 7 p.m. to 4 a.m. shift, handling questions from Canadians about their mortgages and supervising a team of employees, friends and family said.

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