当头一棒 (dāng) — (figurative) a sudden, harsh wake-up call; a severe warning or shock that forces someone to face reality

Definition

Examples

• 老师的话像当头一棒，让他立刻清醒过来。
  Lǎo shī de huà xiàng dāng, ràng tā lì kè qīng xǐng guò lái.
  The teacher's words were like a sudden blow to the head, making him snap out of it immediately.
• 这次失败对他来说真是当头一棒，从此他再也不敢马虎了。
  Zhè cì shī bài duì tā lái shuō zhēn shì dāng, cóng cǐ tā zài yě bù gǎn mǎ hu le.
  This failure was a real wake-up call for him; from then on he never dared to be careless again.
• 父亲的批评给了儿子当头一棒，让他明白了自己的错误。
  Fù qīn de pī píng gěi le ér zi dāng, ràng tā míng bai le zì jǐ de cuò wù.
  The father's criticism was a sharp blow to his son, making him realize his own mistake.