30 Our lawn is frosted over.

我们的草坪上结了一层霜。

But when Arctic temperatures frosted over the Midwest and Northeast, deliveries were suspended in parts of six states on Thursday.

但是当北极的气温在中西部和东北部结霜的时候，星期四六个州的部分地区停止了交货。

So we can use the sentence: it was so chilly this morning that there was frost all over my window.

今天早上太冷了，窗户上满是霜。