例句與造句

1. Gift or " generalized reciprocity " is the exchange of goods and services without keeping track of their exact value, but often with the expectation that their value will balance out over time . " Balanced or Symmetrical reciprocity " occurs when someone gives to someone else, expecting a fair and tangible return at a specified amount, time, and place.
2. It's difficult to find symmetrical reciprocity in a sentence. 用symmetrical reciprocity造句挺難的