《牛津英汉双解大词典》
inure[ɪˈnjʊə, ɪˈnjɔː]verb
[with obj.](一般作 be inured)to accustom (someone) to something, especially something unpleasant使习惯于,使适应于（尤指令人不快的事）
These children have been inured to violence.
这些孩子早已习惯于暴力.
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cause 引起,导致
这里就是“使”的意思,cause to accept 使接受,become hardened to 变得无动于衷.