草船借箭

This is an episode from the Three Kingdoms.

Zhou Yu ordered Zhuge Liang to manufacture 100,000 arrows within ten days. Zhuge said, "Give me three days." He also signed a pledge placing himself liable（有责任的） for punishment should he fail to complete the order. Zhou Yu ridiculed that Zhuge Liang was looking for self-destruction. On the one hand, Zhou Yu ordered his troops not to provide Zhuge Liang with materials to make the arrows. He also sent Lu Su to spy on him to find out what was going on. In fact, Zhuge Liang had already realized that this was a plot by room, Zhuge said to Lu Su, "Save me please." He asked Lu Su to lend him 20boats, each lined with straw-made scarecrows（稻草人） and manned by 30 soldiers. He requested that Lu Su not tell Zhou Yu what was happening.

When Lu Su came again to see Zhuge Liang, he did not find anything unusual. Nothing happened on the second day either. In the small hours of the third day, Zhuge Liang invited Lu Su for a boat ride. The 20 boats were tied together with strong ropes. Zhuge's fleet sailed toward the camp of Cao Cao. A thick mist had spread over the surface of the river. People could hardly see each other on the river. When Zhuge's fleet got close to the Cao camp before dawn, Zhuge Liang ordered his soldiers to shout and beat drums to fake an attack. Zhuge and Lu Su simply sat inside one of the boats and drank wines to enjoy themselves.

As soon as the Cao camp heard the shouting and drum beating, they mistook it for a surprise attack by the Zhou Yu camp. Since they could see nobody on the river, they gathered 3,000 bow men and ordered them to shoot arrows towards where the shouting and drum beating came. The front of the scarecrows was quickly shot full of arrows. After a while, Zhuge Liang had his fleet turned around to expose the other side of the scarecrows. When this side was also shot full of arrows, the day broke. Zhuge Liang ordered his soldiers to return to their base port. The soldiers shouted, "Thank you, Cao Cao, for your arrows." After they got back to their camp, they collected more than 100,000 arrows from the scarecrows.