Elvis Costello What's So Funny About Peace Love and Understanding
https://m.youtube.com/watch?v=J7czbt8tKPg

You mention four skills - speaking,  listening,  reading and writing.   I don't know where vocabulary fits in there or if it should be considered a fifth skill, but without it we have none of the others.

It is not unnatural but you need to use "vents" with first person singular. I googled it and found many examples. https://www.google.com/search?q=he+vents+his+unhappiness&oq=he+vents+his+unhappiness&aqs=chrome..69i57.20474j0j4&client=tablet-android-lenovo&sourceid=chrome-mobile&ie=UTF-8

My essay

I was required to write an essay about whether prostitution should be legalized. (It's a quite sensitive topic)
If you can point out the flaws of structure, grammar or choice of words, I would appreciate that.
Here is my essay.

Prostitution is always considered as the sign of corruption and original sign in public eyes, because it stereotypically reminds people of drugs, thefts, or criminal things. However, maybe the fact is not like as you think. Prostitution, to an extent, has the ability to take off social pressure caused by unemployment, housing issues and broken relationship with one’s partner.
Dating back to ancient China, prostitution was legal. There was a place called “Qing Lou” settled as a brothel to provide sexual service for consumers.
In the first place, paying for sex exists as a deal like other commercial trades. As I mentioned before, legalization of prostitution has developed itself into a strong and lucrative industry. As a matter of fact, this industry offers thousands of jobs and a large amount of money for females, especially for those who haven’t got  been educated and who cannot live on their own. Even though it’s unethical to help those women out in such a way, government officials don’t go any bother of racking their brains figuring how to resolve the huge cost resulted from the jobless women.
In a narrowed sense, prostitution moderately decreased the pressure from almost every aspect such as workplace, family and health. Having sex is helpful for releasing clients’ pressure. So it probably contributes to lower suicide rate and less domestic violence. Once they went through the hard time of trials and tribulations, they would be stronger when next time he feels stressed out.
Overall, prostitution inevitably brings some intractable problems, however, from my point of view, the benefits outweigh the flaws. Nevertheless, it’s unlikely for Chinese to legalize prostitution, whose belief is against to the violation of ethics.