pains

It pains me to see so much food wasted.

用法提示：pains 是及物动词 pain 的第三人称单数，表示‘使…痛苦’；句中 it 是形式主语，后面的不定式是真正主语。

The tight bandage pains her arm whenever she moves.

用法提示：pains 是及物动词，主语 the tight bandage 是造成疼痛的原因，宾语 her arm 是疼痛的部位。

Thinking about that mistake still pains him.

用法提示：pains 是及物动词，主语是动名词短语 Thinking about that mistake，宾语 him 是承受痛苦的人。