Reciprocity /ˌres.ɪˈprɑː.sə.t̬i/ n. 互助;互惠;互换
meaning: behavior in which two people or groups of people give each other help and advantages
词源:rec- 表示re- 往回
词源:proc-表示pro-向前
后缀:-ity 名词后缀
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