You might not have copied the sentence completely.
“如何51吃瓜北京朝阳群众热心吃 瓜”
Do not know what does that mean.
But I’d like to explain a bit.
“瓜” here represents “watermelon,”西瓜， literally meaning “western melon.” Clearly, this is not a native Chinese species; the character “西” (west) here signifies its Middle Eastern origin. For example, “胡” (barbarian) in terms like “二胡” (a traditional Chinese string instrument) also has this meaning, indicating it came from the Middle East.
There are many species introduced to China that are not native. For instance, “番茄” (tomato) and “番薯” (sweet potato), where “番” means foreign. So these are not indigenous Chinese crops.
Even chili peppers are not native. They were only widely cultivated in China during the Ming Dynasty.
However, Chinese people love chili peppers just as much as they love——
Watermelons!
The watermelon production in China is so high that… the yield is just immense.
Because of the high water content, they are not easy to transport. So, while watermelons can be relatively expensive in supermarkets—around $3 per 5 kilograms—if you go to the production areas, they are practically free.
Sometimes, they are even used to feed pigs.
I am an outlier among Chinese people,do not like eating fruit,eating watermelons, but my fellow countrymen love this fruit so much that Chinese people refer to themselves as “吃瓜群众” (melon-eating masses).
The phrase means: I’m just here to watch the fun, holding a melon and eating it, while watching the excitement.
“朝阳群众” (Chaoyang masses) refers to another concept.
Chaoyang is a district in Beijing. There are some middle-aged and elderly women there who have helped the police solve many drug cases, especially involving actors and celebrities, as there are many film and TV stars living in that area. This area became a hotspot for drug problems.
Later, “Chaoyang masses” evolved into a term for “enthusiastic informants who report drug use,” and eventually became known as “China’s most powerful intelligence agency”! People joke that the U.S. has the CIA, the Soviet Union had the KGB, and China has the “Chaoyang masses.”
That’s how it is.