Old friends reunite after 26 years in a sandy land forest their kindness helped grow

What can a 5,000 USD donation nurture over 26 years? For Ronald Sakolsky, a retired American teacher who once taught in Luoyang, a city in central China, the answer is a vast green rising from Maowusu Sandy Land, located in Ordos of north China's Inner Mongolia.
In 1999, Sakolsky learned about Yin Yuzhen and her relentless efforts in fighting desertification through tree planting at Maowusu. Inspired by her commitment, he raised and donated 5,000 US dollars to support her afforestation work. In the second year, his colleague Bai Fan, now general principal of Luoyang No.2 Foreign Language School Education Group, accompanied Sakolsky to Maowusu, where they met Yin in person. Their shared dream of turning sand into green began to take root.
In the years that followed, Yin transformed Sakolsky's donation into a thriving forest. This year, she reconnected with him and invited him back to the sandy land to see how it had changed. On August 24, outside Yin's home, Sakolsky and Bai reunited after 26 years. How did the two old friends greet each other?