痛苦 (tòng kǔ): 고통.

After his relative passed away, he felt extremely painful inside and shut himself in his room all day, unwilling to see anyone.

The end of this relationship made her suffer for a long time; every time she heard that old song, she couldn't help but cry.

The wound after surgery was still painfully tormenting him; even turning over gently required someone else's help.

After losing his job, he not only fell into financial difficulty but also suffered greatly mentally, often suffering from insomnia all night.

Seeing the painful expressions of the children in the disaster area, the volunteers became even more determined to help them.