Because of this comets are often called 'dirty snowballs.'

由此，彗星常被称为“肮脏的雪球”。

And then it just snowballs from there.

然后情况会像滚雪球一样愈演愈烈。

But as a verb, snowball is very different. When a problem snowballs, it grows very big, very quickly.

但是作为动词，snowball的意思完全不同。当一个问题发酵，它会迅速恶化。

We throw snowballs at each other, screaming and laughing.

我们互相扔雪球，叫着，笑着。

So it's just going to sort of snowball.

这就像滚雪球一样。

" It is the boy who threw the snowball, " said my father.

“就是那掷雪球的孩子。” 父亲说。

If you take a snowball and heat it up, it'll melt.

如果你把雪球加热，它就会融化。

The answer is one of those dirty snowballs in space, a comet.

答案是太空中的“脏雪球”之一——彗星。

We were like little children-we made snowballs, and threw them at one another!

我们就像孩子一样——我们做雪球，并用它来打雪仗！

What fun it is to throw snowballs, and to skate on the ice!

打雪仗和滑冰多么有趣！

Have you ever tried to make a snowball but it wouldn't stay together?

你有没有试过捏雪球，但是就是捏不出一团？

In fact, astronomers sometimes call comets “dirty snowballs, ” which isn't a half-bad term.

事实上，天文学家有时称彗星为“脏雪球”，这个词还不赖。

So this highlights the opportunity for a virtuous cycle where the effect can snowball.

因此，这突显了良性循环的机会，在这种循环中，影响可能会像滚雪球一样越来越大。

Number eight is throwing snowballs, as a kid growing up in Canada, snowball fights were super common.

第八条是扔雪球。作为在加拿大长大的孩子，打雪仗是非常常见的。

I want to be able to throw a snowball without getting in trouble, he said.

“我希望能够在不陷入麻烦的前提下打雪仗。”

When Rowley came over, we started rolling the first snowball to make the base.

罗利一到，我们便开始滚第一个雪球，做底下的大球。

In the moment, those changes feel uncomfortable, but each small sacrifice snowballs into a long-term reward.

这些变化会有那么一刻，使人感到不舒服，但每一个小小的牺牲都会累积成长期的回报。

In other words, stop the snowball from rolling.

换句话说，就是阻止雪球滚动。

Because a comet is this dirty snowball of not only rock, but rock mixed with ice.

因为一颗彗星实际上就是一些冰雪物质和尘埃混杂在一起的脏雪球。

Now and then these “dirty snowballs” begin to orbit the sun, just as the planets do.

这些“脏雪球”时不时会开始绕着太阳旋转，就像行星一样。