@Yadan Ma
I am Chinese, 44 years old this year. My childhood spanned the entire 1980s and 1990s. When it comes to maintaining cleanliness, this question brings back some memories of a "dirty and chaotic China."
The first memory is a small detail. In any indoor place in China today, whether it's a restaurant, hotel, or home, every room will have a plastic trash can. There will be a plastic bag lining the trash can to make it easy to remove the garbage. They usually look like this:

我是中国人，今年44岁。我的童年跨越了整个20世纪80年代和90年代。说到保持清洁，这个问题让人回想起“脏乱差的中国”。
第一个记忆是一个小细节。如今在中国的任何室内场所，无论是餐厅、酒店还是家庭，每个房间都会有一个塑料垃圾桶。垃圾桶内衬有一个塑料袋，以便于清除垃圾。

However, these things were not part of my childhood memories. In other words, decades ago in China, there were no such trash cans. So, how did people throw away garbage in rooms back then? My memory is that people either put the trash in a shared outdoor trash can or threw it on the ground inside the room. Once the trash on the ground accumulated enough, they would then throw it into the large outdoor trash can.

然而，这些事情并不属于我的童年记忆。也就是说，几十年前的中国，还没有这样的垃圾桶。那么，当时人们是如何扔房间里的垃圾的呢？我的记忆是，人们要么把垃圾放在共用的室外垃圾桶里，要么扔在房间里的地上。地上的垃圾积累到一定程度后，他们就会将其扔进户外的大垃圾桶里。

Moreover, there is an evolving version of this small detail: I remember when I just got married in 2005, the plastic bags used to line trash cans were the ones from the vegetable markets. People collected these plastic bags after buying vegetables and used them in their trash cans. No one would buy plastic bags specifically for trash cans.
But today, various types and sizes of trash bags are essential in every Chinese household. The most popular ones are the trash bags that, when full, have two drawstrings on the sides that can be pulled to close the bag. This way, you can lift the heavy trash without worrying about it spilling:

而且，这个小细节还有一个演变版本：我记得2005年我刚结婚时，用来装垃圾桶的塑料袋是菜市场的塑料袋。人们购买蔬菜后收集这些塑料袋，并将其放入垃圾桶中。没有人会购买专门用于垃圾桶的塑料袋。
但如今，各种类型和尺寸的垃圾袋已成为每个中国家庭的必备品。最受欢迎的是垃圾袋，装满后，侧面有两条拉绳，可以拉动以关闭袋子。这样，您就可以抬起重垃圾而不必担心它溢出：

My second memory is about littering. I remember when I was in elementary school, around 1992. My mother took me to a newly built park. As we walked, I was eating peanuts and casually throwing the shells on the ground.
A sanitation worker stopped me, but my mother argued with her because she didn't see a problem with throwing peanut shells on the grass. We thought that even if we didn't litter, the wind would blow leaves onto the grass. Prohibiting littering was a common slogan on radio, newspapers, and television in China at that time. It’s important to note that because people didn't care about environmental cleanliness, the government used all mass media to educate the public.

我的第二个记忆是关于乱扔垃圾的。记得1992年左右，我上小学的时候，妈妈带我去了一个新建的公园。一边走，我一边吃着花生，随手把花生壳扔在地上。
环卫工人拦住了我，但我妈妈却和她争论，因为她不认为把花生壳扔在草地上有什么问题。我们以为即使我们不乱扔垃圾，风也会把树叶吹到草地上。禁止乱扔垃圾是当时中国广播、报纸、电视上常见的口号。值得注意的是，由于人们不关心环境清洁，政府利用所有大众媒体来教育公众。

This situation didn't significantly improve even by the late 1990s. In 2000, a Chinese TV station released a popular crime drama called "The Struggle Between Black and White," which depicted the solving of a dismemberment case. The most intriguing aspect of this series was that it featured almost no professional actors! Nearly all the key roles were played by ordinary people, and all the police officers and detectives were the actual officers who solved the case.
Since this drama was released in 2000, it reflected the urban landscape of China at that time. The city in the show had a fictional name, "Beihuan City," but everyone who watched it could recognize it as xi'an, the city with the Terracotta Army. You could see paper scraps, plastic bags, and other trash flying along the main roads of the city.

即使到了20世纪90年代末，这种情况也没有明显改善。 2000年，中国一家电视台推出了一部热门犯罪剧《黑白之争》，讲述了肢解案件的侦破。这个系列最有趣的一点是它几乎没有专业演员！几乎所有的关键角色都是普通人扮演的，所有的警察和侦探都是真正破案的警察。
该剧自2000年上映以来，反映了当时中国的城市风貌。剧中的这座城市有一个虚构的名字“北环城”，但每个看过它的人都能认出它是西安，一座有兵马俑的城市。你可以看到纸屑、塑料袋和其他垃圾沿着城市的主要道路飞舞。

In today's China, littering is unthinkable. If someone throws a piece of waste paper on a commercial street, people will consider them uncivilized. Within minutes, a sanitation worker will pick it up and throw it into a trash can. A few years ago, a moving car threw a pile of shredded paper out the window. A highway cleaner witnessed this and recorded it on his phone, uploading it online, which sparked public outrage. Eventually, the police used roadside cameras to identify the offender, fined him, and demanded a public apology.

在今天的中国，乱扔垃圾是不可想象的。如果有人在商业街上扔一张废纸，人们会认为他不文明。几分钟之内，环卫工人就会把它捡起来，扔进垃圾桶。几年前，一辆行驶中的汽车将一堆碎纸扔出窗外。一名高速公路清洁工目睹了这一幕，并用手机记录下来并上传到网上，引发了公愤。最终，警方使用路边摄像头识别了肇事者，对他处以罚款，并要求其公开道歉。

My child was born in 2010. If he generates trash while playing outside and can't find a trash can, he will keep the trash with him until he gets home to throw it away. Once, he had a runny nose and spent an afternoon playing in the community park. When he returned home, all four of his pockets were filled with used tissues. I asked him why he didn’t throw them in the park's trash cans, and he replied that the park was under renovation and the trash cans were temporarily unavailable.

我的孩子是2010年出生的，如果他在外面玩耍时产生垃圾，找不到垃圾桶，他就会把垃圾留在身边，直到回家再扔掉。有一次，他流鼻涕，在社区公园玩了一下午。当他回到家时，他的四个口袋里都塞满了用过的纸巾。我问他为什么不扔到公园的垃圾桶里，他回答说公园正在装修，垃圾桶暂时没有。

My third memory is about vegetable markets. Up until 2005, going to an open-air farmers' market was a challenge. You had to walk on rotting vegetable leaves, wade through the waterlogged seafood section, and endure the nauseating smell of the poultry area just to buy ingredients. In the past decade or so, such farmers' markets have almost disappeared in China. They have been transformed into tall, specialized buildings, with floor-cleaning machines constantly sweeping the floors, and water flowing through specially designed hidden pipes into the city's sewage system. Today, farmers' markets are almost indistinguishable from supermarkets, equipped with elevators, central air conditioning, ventilation systems, Wi-Fi, and each shop having its own independent water supply system.

我的第三个记忆是关于菜市场的。 2005年之前，去露天农贸市场还是一个挑战。为了买食材，你必须踩着腐烂的菜叶，涉水穿过被水淹没的海鲜区，忍受家禽区令人作呕的气味。近十几年来，这样的农贸市场在中国几乎消失了。它们被改造成高大的专门建筑，地板清洁机不断地清扫地板，水通过专门设计的隐藏管道流入城市的污水系统。如今，农贸市场与超市几乎没有什么区别，配备了电梯、中央空调、通风系统、Wi-Fi，每个商铺都有自己独立的供水系统。

My fourth memory is about public restrooms. The relationship between Chinese people and public restrooms could fill an entire book, as there are many legendary stories. When I was a child, public restrooms did not have flushing systems. Everyone, regardless of gender, had to squat over two concrete slabs. If you weren't careful, you might splash yourself.
Workers would clean the waste once a day. In the summer, Chinese public restrooms would become an unforgettable experience for anyone. In 2006, I bought a book called "Foreigners' Views on China." Some foreigners' most painful memories of China at that time were about "using public restrooms."

我的第四个记忆是关于公共卫生间的。中国人与公厕的关系可以写满一本书，有很多传奇故事。当我还是个孩子的时候，公共厕所没有冲水系统。每个人，无论性别，都必须蹲在两块混凝土板上。如果你不小心的话，你可能会溅到自己身上。
夏天，中国的公厕将成为任何人难忘的经历。 2006年，我买了一本书，叫《外国人眼中的中国》。当时一些外国人对中国最痛苦的记忆就是“上公厕”。

Today's public restrooms in China are quite a different story. Over the years, as I've traveled across the country with my family, we've encountered all sorts of interesting restrooms. Some restrooms have real-time status systems that show which stalls are occupied. Some provide tissues via QR code scanning. There are even restrooms equipped with sofas and coffee tables for people to wait comfortably. A significant number of public restrooms have "family toilets" designed for family members assisting elderly or young children.

如今中国的公共卫生间却是另一番景象。多年来，当我和家人一起走遍全国时，我们遇到了各种各样有趣的厕所。有些卫生间有实时状态系统，显示哪些隔间已被占用。有些通过扫描二维码提供纸巾。卫生间里甚至还配备了沙发和茶几，供人们舒适地等待。相当多的公共卫生间设有“家庭厕所”，专为帮助老人或幼儿的家庭成员而设计。

This summer, we traveled to Qinghai Province in northwest China. The G310 national highway winds through the desolate mountains of Gansu Province for over 100 kilometers. Sometimes, we didn't see another car for half an hour, and I had to make twelve consecutive turns to find a 500-meter straight stretch of road. This area is known for the Qinling Mountains. One afternoon, we stopped at a roadside public restroom in the middle of nowhere, not even near a village. Surprisingly, it was a well-appointed restroom, equipped with large mirrors, washbasins, stainless steel faucets, and running water. Though I'm not sure if it was tap water or spring water, in the 37°C heat that day, the water felt ice-cold on my hands. The restroom had four rooms: men's, women's, a "handicapped toilet," and a "management room." It had a functional flushing system, clean tile floors, intact stalls, and a working ventilation system.

今年夏天，我们去了中国西北部的青海省。 G310国道蜿蜒穿过甘肃省的荒山，全长100多公里。有时，半个小时都没有看到另一辆车，我必须连续转十二个弯才能找到一条500米的直路。该地区因秦岭而闻名。一天下午，我们在一个路边的公共厕所前停了下来，这个厕所位于一个偏僻的地方，甚至不靠近村庄。令人惊讶的是，这是一个设施齐全的卫生间，配有大镜子、洗脸盆、不锈钢水龙头和自来水。虽然不知道是自来水还是泉水，但那天37℃的高温下，水摸到手上感觉冰凉。洗手间有男厕、女厕、“残疾人厕所”、“管理室”四个房间。它有一个功能齐全的冲水系统、干净的瓷砖地板、完整的隔间和一个工作的通风系统。



So, if I were to explain why China is a clean country today, I would summarize based on my experiences: First, extensive and improved infrastructure means people don't need to dirty the environment to use the restroom or buy groceries. Second, trash cans, including recycling bins, are everywhere in cities and towns, so people don't have to search for them. Third, if everything is clean, people are less likely to litter out of embarrassment. In conclusion, China is becoming an increasingly clean and orderly country.

所以，如果让我解释为什么今天的中国是一个干净的国家，我会根据我的经验总结：首先，广泛且完善的基础设施意味着人们不需要污染环境来使用厕所或购买杂货。其次，垃圾桶，包括回收箱，在城镇里随处可见，因此人们不必寻找它们。第三，如果一切都很干净，人们就不太可能因为尴尬而乱扔垃圾。总而言之，中国正在成为一个日益清洁、有序的国家。