beating是动名词还是现在分词?

beating ['bi:ti?] 动词beat的现在分词

adj. 责打, 笞打, 打败, 败北

n. 搅打, 敲, 失败

例句:

He's alive his heart is still beating.

他还活著--心脏还在跳。

We heard the drums beating.

我们听到了敲鼓的声音。

Somebody was beating at the door.

有人不停地敲门。