It's that time of year when people need to lock their cars．It's not because there're lots of criminals stealing cars．Rather，it's because of good-hearted neighbors who want to share their harvest．Especially with this year's large crop，leaving a car unlocked in my neighborhood is an invitation for someone to stuff it with zucchini-a kind of dark green skin vegetable．
My sister，Sharon，recently had a good year of tomatoes．She and her family had eaten and canned so many that they begun to feel their skin turn slightly red．She decided to share her blessings．She called everyone she knew．When that failed，she began asking everyone in the neighborhood，eventually finding a neighbor delighted to have the tomatoes．"Feel free to take whatever you want，"Sharon told her．She felt happy that she could help someone and that the food didn't go to waste．
A few days later，the neighbor appeared in her house，holding a hot loaf of bread．She smiled，"I wanted to thank you for the tomatoes，and I have to admit I took a few other things too．"
Sharon couldn't think of anything else that had been worth harvesting．The neighbor went on saying，"You had some of the prettiest zucchini I've ever seen．"
Sharon was confused．They hadn't even planted any zucchini．But her neighbor insisted there were bright-green zucchini in her garden．Sharon decided to go to see where the zucchini had grown．The two of them walked into the backyard．When the neighbor pointed at the long green vegetables，Sharon smiled，"Well，actually，those are cucumbers that we never harvested，because they got too big，soft and bitter for eating．"
The neighbor looked at Sharon，shock written all over her face．Then，smiling，she held out the bread she had shared all over the neighborhood．"I brought you a nice loaf of cucumber bread．I hope you will like it．"
21．What does the underlined word"stuff"in Paragraph 1probably mean？___