Since ancient times people have found various ways to preserve meat.

单选题

Since ancient times people have found various ways to preserve meat.

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单选题

Over five times more studies on life satisfaction have been published since 1979 than at any time_____

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填空题

ancient（）

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单选题

In ancient times wealth was measured and exchanged in things that could be touched:food,tools,and precious metals and stones.Then the barter system was replaced by coins,which still had real value since they were pieces of rare metal.Coins were followed by fiat money,paper notes that have value only because everyone agrees to accept them.Today electronic monetary systems are gradually being introduced that will transform money into even less tangible forms,reducing it to a series of“bits and by

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单选题

Since there are so many cars on the road, _____ many hours to complete a short journey at peak times in some major cites.

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