Remember, the movie was released in 1968, when the U.S. had a very active space program.

请记住， 这部电影于 1968 年上映，当时美国的太空计划非常活跃。

It probably comes from the 1960s and 70s, when the United States had an active space program.

它可能来自 1960 年代和 70 年代， 当时美国有一个活跃的太空计划。

U.S. President Donald Trump says Beijing should use that leverage to force Pyongyang to dismantle its increasingly active nuclear weapons program.

美国总统唐纳德特朗普表示，北京应该利用这一影响力迫使平壤取消其日益活跃的核武器计划。

So, bats use echolocation to get around and some birds navigate by the stars, but there's not an active research program seeing if cats can use echolocation or dogs could navigate by the stars.

因此，蝙蝠使用回声定位来四处走动， 一些鸟类则通过星星导航，但目前还没有一个活跃的研究计划来看看猫是否可以使用回声定位或狗是否可以通过星星导航。