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문제와 답만 있습니다.

(A), (B), (C)의 각 네모 안에서 문맥에 맞는 낱말로 가장 적절한 것은?

Five thousand years ago, the craters of extinct volcanoes in Arabia (A)was/wereused as this by farmers for their irrigation water. Dry climate and water shortage in India led to early development of water management techniques, including the building of this in 3,000 BC. This may be created in river valleys by the construction of a dam or may be built by conventional construction techniques, like brickwork. This is used to (B)provide/providingraw water feed to a water treatment plant which (C)deliver/deliversdrinking water through water mains. This does not simply hold water until it is needed; it can also be the first part of the water treatment process.

( A )                  ( B )                     ( C )

① was           provide               deliver

② was         providing             deliver

③ were         provide               delivers

④ were        providing              deliver

⑤ were        provide               delivers