While they were laughing and talking, Huai Zi suddenly took Juhua's hand. He saw her hands were stained with sap, which had mixed with dust and turned a grimy black. He opened his mouth, wanting to say something, but then he saw his parents were also busy. 'I can't very well say I don't want my wife getting her hands dirty, can I?' The sap from the sweet potato vines was particularly difficult to wash off; it was so sticky you couldn't even scrape it away.
So he said to Juhua, "You do the cutting. I'll straighten and tie the bundles."
When you did the cutting, you wouldn't get any sap on you as long as you didn't touch the cut ends. But bundling them required you to straighten the vines by hand, which made it easy to touch the fresh cuts and get sticky sap all over your fingers.
