A graduation ceremony photo taken in 1974 shows 50 Sudanese trainees with their Chinese teachers. [Photo provided to China Daily]

Apart from "Mother Yao", "Father Zeng", whose real name is Zeng Qinglin, was another star Chinese instructor. And Yasir Mohamed Musa Abdelrahman was one of his trainees.

The 50-year-old man expressed his gratitude for "Father Zeng" on many occasions.

Abdelrahman's parents were not willing to send him to learn acrobatics initially, as they thought it was too dangerous and their son may be out of work after returning.

Zeng had to talk to his parents several times to persuade them, and they were moved by the Chinese coach's sincerity.

At present, Abdelrahman serves as the permanent acrobatics coach in Sudan and helps many locals realize their acrobatics dreams.

"To be honest, I was a little afraid of 'Father Zeng' in the beginning, as he was strict in his teaching. But because of him, I have realized the smallest negligence in daily training could lead to disaster in stage performance," he said. "However, he was a considerate man. He once took the whole class to the Lushan Mountain scenic spot, and I loved the spectacular natural scenery there."

Zeng turned 81 in 2018, but he still remembers those Sudanese acrobats.

"I have been teaching acrobatics for more than four decades, and the promotion of Chinese acrobatics in African countries is definitely the thing I would like to be remembered for most," Zeng told China Daily.

Zeng managed to train three batches of Sudanese acrobats in the 1970s, contributing to the birth of the first national-level acrobatic troupe in Sudan.