补全短文supermarket
supermarket is a type of retailing institution that has a moderately broad product assortment spanning groceries and some nonfood lines， that ordinarily emphasizes price in either an offensive or defensive way. as a method， supermarket retailing features several related product lines， a high degree of self-service， largely centralized checkout， and competitive prices. the supermarket approach to retailing is used to sell various kinds of merchandise， ____(1)____。
the term supermarket usually refers to an institution in the grocery retailing field. most supermarkets emphasize price. some use price offensively by featuring low prices in order to attract customers. other supermarkets use price more defensively by relying on leader pricing to avoid a price disadvantage. since supermarkets typically have very thin gross margins， they need high levels of inventory turnover to achieve satisfactory returns on invested capital.
supermarkets originates in the early 1930s. they were established by independents ____(2)____。 supermarkets were an immediate success， and the innovation was soon adopted by chain stores. in recent decades supermarkets have added various nonfood lines to provide customers with one-stop shopping convenience and to improve overall gross margins.
today stores using the supermarket method of retailing are dominant in grocery retailing. however， different names are used to distinguish these institutions ____(3)____：
a superstore is a larger version of the supermarket. it offers more grocery and nonfood items ____(4)____。 many supermarket chains are emphasizing superstores in their new construction.
combination stores are usually even larger than superstore. they， too， offer more groceries and nonfoods than a supermarket but also most product lines found in a large drugstore. some combination stores are joint ventures between supermarkets and drug chains such as kroger and sav-on.
for many years the supermarket has been under attack from numerous competitors. for example， a grocery shopper can choose among not only many brands of supermarkets but also various types of institutions (warehouse stores， gourmet shops， meat and fish markets， and convenience stores)。 supermarkets have reacted to competitive pressures ____(5)____： some cut costs and stressed low prices by offering more private brands and generic products and few customer services. others expanded their store size and assortments by adding more nonfood lines (especially products found in drugstores)， groceries attuned to a particular market area (foods that appeal to a specific ethnic group， for example)， and various service departments (including video rentals， restaurants， delicatessens， financial institutions， and pharmacies)。
a by size and assortment
b than a conventional supermarket does
c including building materials， office products， and， of course， groceries
d attracting more customers with their low prices
e primarily in either of two ways
f to compete with grocery chains
keys： cfabe