He will be in a long-distance relationship with his girlfriend after joining the Marines.

VOA: special.2009.09.14

Then that's not a very long distance, probably easily walkable in a few minutes; but that child can't be walking through everybody's yard.

他们离得不远,可能走几分钟就到了,但是你的孩子却不能直接走到他的朋友家

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

How long" can be used in a question and it refers to a length of time or a length of distance.

How long” 句型用于问句中，用来询问时间或距离的长短。

How long课堂 - SpeakingMax英语口语达人

In my childhood I had to walk a long distance to go to school.

VOA: standard.2010.04.01

And the telephone companies in the United State, generally about 200 billion dollars a year carrying long distance telephone conversations and they thought this conversations might be carried for free over the internet was quite shocking to them. Of course free is very low price, and they are not like it to be free.

美国的各电话公司，一般大约有每年2千亿美元,来自长途电话会话，他们认为,这些会话有可能通过互联网免费传输,对他们来说是相当震惊的，当然了,免费是很低的价格了，他们不希望它免费。

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