(1)(使)變硬(堅強，強壯)((cause sth or oneself to) become hard， firm or stiff，stronger and more able to deal with difficulty)[I，T+n]：The snow/chocolate/glue～ed. 雪/巧克力/膠水變硬了。His mind～ed.他的心腸硬了起來。The opposition to the military government～s. 對軍政府的反抗強硬起來?！玦n one's resolve 堅定了自己的決心;～the defences加強防御;～the steel/the clay使鋼/泥土變硬;～one's body/one's heart使身體強壯/心腸硬起來;～hold on the door更緊地抓住門;～sb considerably 使某人堅強了許多;
(2)使變得冷酷(麻木)(make sb less sensitive to sth)[尤pass：T+n，T+n+prep (to)]：be/become～ed to failure/the sight of blood/the suffering around oneself 對失敗/見到血/周圍人的痛苦變得無動于衷;a～ed criminal 死不改悔的罪犯;
【用法】harden只用于表示“堅硬，堅強”或“嚴(yán)酷，苛刻”，例如：leave the wet cement to harden(讓濕的水泥硬起來);She hardened her heart.(她硬起心腸來。)在其他場合用get hard(er)，例如：The exercises in this book gradually get harder.(這本書的練習(xí)逐漸變難。)Life is getting hard for people on low incomes.(低收入者的生活變得艱難起來。)