21. а) Раскройте скобки и употребите глаголы в соответствующей форме.
Each market (to describe) by two main characteristics: the good itself and the geographic area. Each market (to include) only the goods which (to satisfy) the same consumers' needs. For example, two brands of English muffins (сдобные булочки) (to be) in the same market, but televisions and cars (to be) in different markets. Nintendo and Sony electronic games (not to be) identical goods, but they both (to include) in the market for games.
The second characteristic of a market, geographic area, (to be) also of importance for describing markets. As bread (to bake and to sell) usually in a particular place, the Chicago bread market and the Detroit bread market (to be) different markets. As microwave ovens (to transport) nationwide, the market for a particular brand (to be) the entire country or several countries.