Polar mesospheric, or noctilucent ("night shining"), clouds usually are seen at twilight, following the setting of the sun below the horizon and darkening of Earth's surface.

极地气层云，或者说晚霞，通常是那些在黎明前看到的云朵，伴随着地平线以下落幕的太阳和黑暗的地球表面。

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We have seen, of the flowers, and the swallows, the setting sun and the rising moon, and all sorts of important things.

我们已经知道，谈花、燕子、落山的太阳、初升的月亮，所有这一类重要的东西。

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With a sense of panic setting in across Hollywood, the industry has, in the past three months, seen the biggest shake-up of studio chiefs in 25 years.

随着恐慌感在好莱坞逐渐弥漫，在过去三个月内，制片业界经历了25年来最大的总裁人事震荡。

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The BBC News Channel's chief political correspondent Norman Smith said it was no surprise the Labour leader was trying to pin the UK's economic woes directly on No 10 as all the leaders sought to gain the initiative ahead of what is being seen as a crucial week in setting the political agenda.

BBC: Coalition needs 'answers not excuses' says Ed Miliband

Over the last few years Grech-Cumbo has seen the blanket approach to goal-setting among many corporations change.

CNN: Goal rush: Why goal-setting isn't always a good thing

Arrowe Park hospital, in the Wirral, has seen some impressive results from setting up systems to share information every month with the police and local council.

BBC: Many hospitals not sharing crime data, audit shows