In ancient China, people passed down plenty of classic stories from generation(一代人) to generation. Here are the stories of two famous characters.
One person is Che Yin. He was from a poor family, but he loved studying. He had to work in the daytime, so he could only study in the evening. However, there was a problem. He couldn't afford a lamp(灯). He didn't worry about that in summer. In the evening, he caught some fireflies (萤火虫), put them in a bag and used it as a lamp. This lamp was not very bright, but Che Yin could do some reading by lamplight in the evening.
The other person is Sun Kang. He was smart, but he was so poor that he couldn't go to school. So he studied at home. He had to read just at night. Like Che Yin, he couldn't buy a lamp. On snowy nights, he went out and read in the snow. Why? There was the light of snow outside.
Later, people use "Nang Ying Ying Xue" to say that a strong spirit is very important no matter how hard the life is. When we are having a hard time in life, don't lose heart. Never let life knock us down. Even in the hardest situation, there is hope that encourages us to move forward.