円錐形

​雪在我们印象中一直是洁白无瑕的，但是近日东欧多个地区却惊现“橙色雪”，这场可怕的橙色暴风雪将大片雪白的山脉变成了赤褐色，火星般的场景让人怀疑是末日降临。那么这种诡异的颜色是如何形成的?来看看气象学家怎么说。

Although it resembles what we might imagine snow on Mars to look like, the explanation is actually pretty simple.A recent fall of really strange orange-tinted snow is making headlines after it swept across a swathe of Eastern Europe. Images on social media from Russia show mountainous landscapes tinged auburn, where usually they are pristine white.

最近东欧多地上空飘起橙色雪，这一奇特景象抢占了新闻头条。俄罗斯社交媒体的图片显示，往常雪白的大片山脉被染成了赤褐色。

尽管它看上去像极了我们想象中的“火星雪”，但是这个现象背后的原因其实很简单。

According to the BBC, the orange colouration is caused by fine particles of sand being lifted from the Sahara into the atmosphere, travelling across the world and falling back to the ground mixed in with rain and snow.

据BBC报道，雪的橙色调源于撒哈拉沙漠飘来的细沙，这些细沙经历了“环球旅行”，最后混在雨雪中降落到地面。

学了这么多年英语，你真的会使用英文中的撇号吗?各种所有格和动词缩略语怎么写又是正确的呢?来看看知名英文学习视频博主Lucy怎么说。

YouTube视频栏目“跟露西学英语”的博主露西-厄尔最近发布了一段视频指南，帮助英语学习者和英语为母语的学生。

露西逐条分析了撇号的常见用法，包括动词缩写和所有格，还讲了大家最常犯的错误。

The possessive case

所有格

The possessive case is used to show a relationship of belonging between one thing and another.

所有格形式用来表述两件事物之间的归属关系。

To form the possessive, an apostrophe and an 's' is added to the noun. For example, if a ball belongs to the dog it is the dog's ball.

为了构成所有格，名词后面要加撇号和s。比如一个球属于一只狗，那就是dog's ball。