On Saturday, he and his graying-but-vibrant students will perform at the 17th annual Mid-Autumn Festival, expected to draw 5,000 to Chinatown from across the Philadelphia region for kung fu exhibitions, Peking opera, health screenings, and a moon cake-eating contest.
The organizers have honored Mark's three decades of service to Chinatown by awarding him a permanent performance slot in the festival, which has shortened its hours, pushing most acts onto an every-other-year rotation. In this neighborhood, he is teacher, helper, volunteer, advocate, father, and friend.
Twice a week, after his morning class, Mark heads over to teach at On Lok House, the Chinatown home for the elderly and disabled. Other days, he's at a planning session for a project or cause - he took a strong hand in protests that helped derail plans to build a baseball stadium and a casino in Chinatown.
"He's the kind of person who is really important to our community, because he gives of himself in ways that make the community stronger," said Ellen Somekawa, executive director of Asian Americans United, which puts on the festival. "He does things out of love and concern and care and selflessness."
Mark, in an interview at his Chinatown rowhouse, said he doesn't want to hear all that stuff about his being caring and concerned. He'd rather talk about tai chi.
An ancient art
The art is ancient, known in China as early as the third century. Buddhist monks performed a version that pantomimed the graceful, athletic movements of forest animals - bird, tiger, monkey. Today the low-impact, mind-and-body martial art is practiced both for defense training and for health.
The motions tend to be slow and circular, with names such as "Carry Tiger and Return to Mountain" and "Wave Hands Like Clouds."
In China, it's common to see large groups performing in public parks and parking lots. Some incorporate fans or mock swords. Proponents say the practice unblocks qi, the energy force that flows through the body, and promotes the balance of yin and yang.
Western scientists don't subscribe to the ebb and flow of qi. But they do say there's evidence that tai chi can help treat and prevent health problems. Authorities at Harvard Medical School say tai chi promotes muscle strength, balance, and flexibility, and can be adapted to help people who use wheelchairs or are recovering from surgery.
Mark began his journey to tai chi in 1964, when he took classes in another martial art, karate. Four years later, at 44, he earned his black belt. But as he aged, he realized he couldn't continue to inflict - and absorb - the strikes and kicks.
He could, however, learn the deliberate movements of tai chi. He began studying in 1980, intrigued by the art's demand for concentration, wondering about its ability to promote mental clarity among elderly practitioners.
"The older people feel it does some good for them," Mark said, sitting surrounded by photos of his wife, now gone, and their seven children. "In karate, you punch me, I punch you back. In tai chi, you punch me, I turn your force against you."
Mark's family hailed from Guangdong province. His grandfather came first to the United States, followed by Mark's father. Mark was born in Philadelphia in 1924, in a 10th Street home two doors from what is now the Imperial Inn restaurant.
At that time, Chinatown wasn't yet Chinatown - merely a few businesses clustered on Ninth Street, where Mark's father kept an office. He was an herbal doctor, dispensing remedies to people who had little money but a strong belief in traditional medicine.
Mark was 5 when his family returned to China, though the stay was not idyllic. Japan invaded in 1937, the start of World War II. Mark and his sister came back to the United States two years later, when he was 15, timing that put him in line for America's entry into the war.
He was drafted in 1943 and sent to basic training at Fort Bragg, N.C. As he and his unit prepared to ship to the Solomon Islands, site of horrendous fighting against the Japanese, Mark was unexpectedly pulled from formation and reassigned.
"I was saved that day," he said, recalling friends wounded or killed in the Pacific. "They fell like trees."
Mark spent the war in a stateside photo lab, taking pictures of German and Italian prisoners. Afterward, he settled in Mississippi, then came to Philadelphia in 1946 and took classes at Temple University.
He worked nearly 20 years in electronics at Radio Corp. of America in Camden, then at Northern Telecom. When he retired in 1987, he became even more involved in the life of Chinatown.
"He's an inspiration," said Debbie Wei, a Philadelphia educator and veteran Chinatown activist.
Mark is among the most senior of community elders, a bank of wisdom, Wei noted. His involvement in protests has encouraged younger generations to stand up for their neighborhood.
"When young people see the commitment he has, they're like, 'We haven't earned the right to rest,' " Wei said. "It's the history that he carries, the sense of community and place."
The first Mid-Autumn Festival was organized by teenagers who sought to soothe the homesickness of the elderly.
Mark's tai chi group performed. He knew what it felt like to miss your home. Later, he joined the festival planning committee. On Saturday, besides performing tai chi, he'll be counting out tickets for carnival games.
For years, the evening lantern parade signaled the start of nighttime entertainment, but now it closes the festival. In 2010, AAU shortened the event because of fights among teenagers.
That pains Mark. The festival is similar to Thanksgiving, a time for families to gather, to be grateful for the people around them and the food on their plates. That's why he's been so active. That's why it's important, he said, for old and young to celebrate.
"They begin to realize what that [day] means to them," he said. "No matter how far away you live, that one day, your family comes back together."
What: Mid-Autumn Festival.
Where: The Friendship Gate at 10th and Arch Streets in Chinatown.
Hours: 12:45 to 6 p.m.
For more information: Asian Americans United, www.aaunited.org or 215-925-1538.
Contact Jeff Gammage at 215-854-2415, firstname.lastname@example.org, or follow on Twitter @JeffGammage.