There are two types of graded funds: Class A and Class B. Class A is a stable share and Class B is an enterprising share. Due to the existence of two different risk shares, the fixed leverage of graded funds is 1. Class b share 1 bear the risk of all losses of the fund. Operationally, Class B shares borrow funds from Class A shares for investment, and it is agreed that 1 will be allocated to Class A. When Class B income is greater than Class A income, Class B shares are positive, and vice versa. Therefore, as long as the fund does not lose money and cannot repay the class A share and its income, the class A share belongs to a risk-free variety. On the contrary, the risk of class B will be transmitted to class A, which will lead to the liquidation of the fund. At the same time, Class A also has the risk of principal loss.