It's the type of book that would make sailors blush, but don't go buying it for grandma. Welcome to the book of Chinese slang.

With chapter titles ranging from "Internet Slang" to "Behaving Badly", Eveline Chao's "Niubi - The Real Chinese You Were Never Taught in School", has got Chinese learners and citizens alike speaking in a more colorful, and sometimes more coarse, vernacular.

More than three years in the making, Chao's book, published late last year, catalogs the underbelly of the Chinese language.

With phrases from "suo tou wugui", a Chinese expression for cowards meaning "turtle with its head in the shell", to "se lang", meaning "color wolf", an expression used to describe an overly aggressive male, to the downright dirty, the book offers adult readers a way to "spice up" their everyday dialogue.

"The key to learning any language well is to create real interest. If you're just taking Mandarin to earn a college credit, you won't take it very seriously," she said. "These kinds of words help make the language much more fun."

She said learning slang also allowed you to discover Chinese culture, because many of the more casual sayings and expressions are lost when written.

"Written Chinese is extremely formal and almost completely different from spoken Chinese," she said. "It's interesting to see how Chinese people really think and how they really speak."

The 30-year-old New Yorker said content for the book was in production long before the idea of making it into a book was proposed.

"Like almost everyone who visits China, when I go out with my friends, I bring a notepad and pen to jot down interesting words or phrases," Chao said.

As the introduction to the book explains, Chao's choice of late night friends resulted with her notebooks being filled with colorful phrases.

The research for the book, she said, was much harder than most people thought, often requiring a huge sacrifice of time and sleep.

"I would receive calls around 1 am from friends telling me they were hanging out with a DJ or someone else I had wanted to interview for the book. I would have to drag myself out of bed, get dressed and go to hang out," she said.

One year and several notebooks later, Chao had amassed a commendable collection of less-than-savory phrases and sultry slang.

It wasn't until a publisher friend in New York contacted Chao that she recognized the potential value of her late-night scribblings.

After a 50-page proposal, rife with risqu phrasings, she had herself a book deal with Plume Publishing, who has published similar books in other languages from its base in New York.

Initially, Chao said the book was geared toward American students studying Chinese in the United States, who were looking to expand their more unconventional vocabulary.

"People living in Beijing might only know a standard set of Beijing slang, so for them, it's a kind of learning experience," she said.

Chao said one of the most educational chapters for her was the one that focused on Internet slang.

"The reason a Chinese slang book has not been written before is because China is so regionalized. Before the Internet, so many of these words were just for locals.

People from certain areas in the south had their slang and people from areas in the north had theirs, too," she said.

"The Internet, in a way, helped bridge these subcultures."

"Slang words are important for culture and are more than just interesting ways to express emotion. They often have deeper social and economic implications."

The book can be found at the Bookworm, Sanlitun and Garden Books, Jianguomen.

While the book may not be found in high school classrooms in the near future, for adults looking to loosen up their Chinese language abilities, it's one to swear by.

China Daily