校園英語口語習慣用語第260期:set one's jaw
set one's jaw 堅持到底
【講解】
jaw的本義是“頜”；動詞set有“使臉部出現堅定不移的表情”的意思。set one's jaw用來形容人把下巴一沉，表現出堅毅不服輸的表情。
【對話】
A:I haven't seen you for a long time. What are you doing?
A:好久不見了，你在幹什麼？
B:I've been keeping on studying the piano.
B:我一直在學彈鋼琴。
A:How's it going?
A:學得怎麼樣？
B:Too bad. I failed the test for degree. So I have to set my jaw to do more practice.
B:糟透了，我等級考試沒過，所以我只好咬緊牙關進行更多的練習。
