猛虎深山

Explanation: Yu Yongwu and is powerful. Sima Qian of the Han language, "Letter to Ren": "Tigers in the mountains, beasts fear of shock." 　　Source: Sima Qian of the Han language, "Letter to Ren," Tigers in the mountains, beasts shock fear. " 　　Examples: Like the people's army - is irresistible.