Complex sentence: Market price is an economic concept with commonplace familiarity; it is the price that a good or service is offered at, or will fetch, in the marketplace; it is of interest mainly in the study of microeconomics.
Split into simpler sentences: Market price is a familiar economic concept: it is the price that a good or service is offered at, or will fetch, in the marketplace. It is of interest mainly in the study of microeconomics.