The messageof【C1】______such as this is【C2】______natural systems are complex, unpredictable

The message of【C1】______such as this is【C2】______natural systems are complex, unpredictable: understanding them【C3】______patient observation and【C4】______analysis. The lack of these conditions explains why, in the early modem era, grass snakes were killed as venomous, and gardeners【C5】______worms because they【C6】______gnaw plant roots.

The assumption that people "ought" to know about such things is based on an urban-rural divide that opened up in the 18th century. For a【C7】______of centuries, city and country people did【C8】______separate realms. But the ear, the phone, the media and the Internet have contributed to the【C9】______tendency of what we call modem lifestyle; and the vast population.【C10】______from cities into rural areas blurred the difference【C11】______urban and rural. Thus, a new word "rurban" —has been coined to【C12】______this condition. Most of us now work【C13】______or in an office, and【C14】______we are involved in our primary industries, we are【C15】______more likely to be staring【C16】______a computer than【C17】______with the landscape. Human life has turned generally into a【C18】______by work, sleep, shopping and TV-all【C19】______identical【C20】______performed in town or country.

【C1】

A．study

B．studies

C．studying

D．studied