they're swelling up hugely 它们大面积地膨胀开来

swell up膨胀

Her ankle swelled up after the fall.

她跌倒后脚踝肿了起来。

Don't prick that boil; allow it to swell up and burst.

不要挑破那个疖子; 让它肿起来自己破裂好了。

investigates what happens to food at the microscopic level when it's cooked.从显微水平上研究食物被烹煮熟后的变化

happen to发生

How could this happen to me!

我怎么会遇到这种事啊！

She places a piece of raw potato under a microscope她将一片生马铃薯置于显微镜下

a piece of一张(片； 块； ... )

Would you please give me a piece of paper?

能给我一张纸吗？

I was hurt by a piece of falling masonry.

我被掉下来的一块建筑用石块砸伤。