每日钉一下（社保基金投资收益的三个来源）

Group 1 - Many investors start their investment journey with index funds [1] - There is a limited-time free course that introduces investment techniques for index funds [2] - To access the course, individuals can add the "Course Assistant" and reply with "Index Fund" to receive it [3] Group 2 - The course includes notes and mind maps to help learners understand the course structure quickly and learn more efficiently [3] - There is an option to click and read the original text for free learning on large family asset allocation courses [4]