For a long time not seen in snowflakes flying.

许久不见雪花飘落了。

youdao

It's not known when Mars was found and by whom Mars has been known for a very long time, and one of the planets that can be seen from the Earth without a telescope.

在很长一段时间里，没人知道火星是什么时候被发现的，谁发现的，也不知道有一种行星可以不用望远镜就能从地球上看到。

youdao

Time is a continuum, I told her, thinking about friends and people that I hadn’t seen for so long, and people I’d never known who might or might not have died in the earthquake.

我告诉她说：“时间是一个一维的连续体，我考虑的是朋友、那些我好长时间都未谋面的人，还有我从未相识的人，在这场地震中，他们也许死了，也许还没死。”

youdao

Later,I got a telephone call from a friend whom I had not seen in a long time.

VOA: special.2009.05.03

"I've been in the job for a long time and seen a few players not come back from similar injuries, " he added.

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She had last seen him Monday morning, when he told her he was planning to drive north to visit his ill godfather who he had not seen in a long time.

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Gooding, who recently returned to Springfield, Missouri, from Swaziland, says he has not seen snow in a long time.

CNN: Shadows aren't just for groundhogs