Your text outlines some fundamental concepts in economics related to the laws of supply and demand. Here’s a concise explanation based on the points you've mentioned while filling in the blanks:
The law of demand describes the relationship between prices and demand. According to this law, higher prices encourage buyers to look for a substitute. A substitute is a roughly equivalent good or service. Finding substitutes drops demand for the original good or service, thus lowering prices over time.
The law of supply illustrates the relationship between price and quantity supplied. A rise in prices encourages producers to supply more of a good or service in the hopes of making more money.
The demand curve visually represents the relationship between the price of a good and the quantity of that good demanded by consumers.
Relative price refers to the price of a good or service in comparison to another, which affects the choice consumers make regarding substitutes.
This interconnectedness among these concepts forms the basis of market dynamics, where changes in price influence both consumer behavior (demand) and producer behavior (supply).