英文：no laughing matter (n.)
說明：這慣用語通常與 BE 動詞連用，放在 BE 動詞之後。
例句：
- Be serious! This is no laughing matter. (別開玩笑了！ 這是正經事)
- Think twice before you adopt that Chihuahua. Taking care of a pet is no laughing matter. (你養那隻吉娃娃之前要想好哦。養寵物可不是開玩笑的)
- This disease is no laughing matter. It’s quite deadly if not treated immediately. (這種病可不是開玩笑的。若不馬上治療，它有相當的致命性)