A year later, Yangzi came home, and his wife knelt down and asked him why he came back. Yang Zi said, "I have been away for a long time, and I feel homesick. Nothing special. " Hearing this, the wife picked up a knife and walked quickly to the loom and said, "These silks are all born from cocoons and woven on the loom. A little at a time, only one inch long, one inch at a time, only a horse. Now, if we cut off these silk fabrics that are being woven, it will not be successful, and it will waste time. If you accumulate knowledge, you must' learn what you don't understand every day' to achieve virtue; If you come back halfway, what's the difference between cutting off this silk? " Yang Zi was moved by his wife's words and went back to finish his studies. He didn't come back for seven years.