土黄，给人辛苦的感觉。工人在飞扬的尘沙中工作，汗水碰到了泥沙滴了下来，成为土黄色的汗，真令人敬仰。绿，是新鲜活泼的象征。穿着鲜绿的衣服，坐在青翠的草地上，观赏草儿随风起舞，耳朵听着微风的伴奏，身心愉快，忘却一切烦恼。白代表纯洁。白色的粉笔，是老师传授知识? Indigenous, giving a hard feeling. Workers working in the dusty sand, sweat hit the sand dripping down, a khaki sweat, it is admirable. Green, is a symbol of fresh and lively. Dressed in fresh green clothes, sitting on the verdant grass, watching the grass dancing in the wind, ears listening to the breeze accompaniment, mental and physical pleasure, forget all the troubles. White represents purity. White chalk, is the teacher imparting knowledge?