- 问题详情: Howdidpeopletellthetimebeforeclockswereinvented?Atfirst,theancientpeoplelookedupatthesunandcouldtellitwasthemiddleofthedaywhenthesunwasdirectlyoverheadinthesky.Theyalsoknewwhenitwasmorningorevening.Later,theEgyptiansusedsticks.Thesestic...
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