One theory is that wolves howl to bond better together.

一种理论认为狼嚎是为了更好地团结协作。

I howled in pain as I dropped the hammer onto my foot.

锤子砸在了我脚上，我疼得大叫。

The wind howled through the trees.

风在林间怒号。

She let out a howl of pain.

她发出了一声痛苦的叫喊。