From the child to old age, we all use language as a means of (36) our knowledge of ourselves and the world around us. When humans first (37) , they were like newborn children, unable to use this valuable tool. Yet once language developed, the (38) for human’s kind’s future attainment and cultural growth increased.
Many linguists believe that evolution is (39) for our ability to produce and use language. They (40) that our high evolved brain provides us with an innate language ability not found in lower organism. Proponents of this innateness theory say that our potential for language is (41) , but that language itself develops (42) , as a function of the growth of the brain during childhood. Therefore there are critical biological times for language development.
Current reviews of innateness theory are mixed, however, evidence supporting the (43) of some innate abilities is undeniable. Indeed, more and more schools are discovering that foreign languages are best taught in the lower grades. (44) .
Although some aspects of language are undeniably innate, language does not develop automatically in a vacuum. Children who have been isolated from other human beings do not possess language. (45) Some linguists believe that this is even more basic to human language acquisition than any innate capacities. These theorists view language as imitative, learned behavior. In other words, children learn language from their parents by imitating them. (46) .

克罗恩病的好发部位是：（）

A.末段回肠和右半结肠

B.乙状结肠

C.左半结肠

D.空肠

E.横结肠