1. Cooperate with them and become a member of their company. How much is a quarter (or half a year)? Generally, it is charged at 10% of your capital.
2. Share 37% (or 46%) with their company, so that you can make money after you earn it.
I have received similar calls from such companies myself, which is completely deceptive. If you really earn a few percent a year as they say, then retail investors in China will get rich. They are well-known not only in China, but also all over the world. I hope you can take precautions yourself and don't trust these so-called "institutions and private placements".