Dear all,Top “how-tos”:
1) How do I deal with a boyfriend exhibiting violent tendencies?
2) What should I do if I’ve consumed ditch oil?
3) How to repair broken porcelain?
4) What do I do if my brother is taken in by a pyramid scheme?
5) What do I do about sleepless nights?
While reading an artcle of 2011 edition of Chinese internet hotspot, I came across the above. Could you please tell me what "pyramid scheme" means here? Thanks.