- 问题详情: Weoftenthinkoffuture.Weoftenwondertheworldwillbelikeinahundredyears’time. Thinkofspace.Perhapsapermanentstationinthemoonwillhavebeensettedup.Perhapspeoplewillbeabletovisitthemoonastourist.Cheaprocketsforspacetravelwillhavebeendeveloped,...
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