Hasn't the ＄10 you lent me been paid back?为什么用been paid back

Hasn't the ＄10 you lent me been paid back?为什么用been paid back my brother hasn't been back yet.=my brother hasn't returned Have you been back to the piace It's high time he paid me back the 100 yuan he owes me.翻译 为什么是It has been paid而不是 It has been paid for? Mary hasn't paid for the school things ,has she? The workers are_____because thier boss hasn't paid them for Tom hasn't come back I wonder what has been happened to him. My uncle went to Beijing last month.And he hasn't been back Zhong Wei hasn't been back in close to three years.（英语问题） -Have you been paid for the painting?-Yes,I remember______$6 tom hasn't been to the Great Wall,has he?为什么回答用No,he hasn't