除了与生俱来的血缘关系外，人际关系的建立、维持都需要投入。人际关系的投入除了满足现时的需要（娱乐、情感交流）外，还可以使这种人际关系能维持和加深，以便在将来的交往中获益。在市场经济条件下，随着知识经济的到来，构建人际关系的目的性会更强，会有更浓厚的投资色 In addition to the inherent blood relationship, the establishment of human relations, maintenance needs to be invested. In addition to meeting existing needs (entertainment, emotional exchange), interpersonal relationships can also enable such relationships to be sustained and deepened to benefit future engagement. Under the condition of market economy, with the advent of a knowledge-based economy, the purpose of building relationships will be stronger and there will be a stronger investment color