| 痛苦HSK 5 | tòng kǔ | pain; suffering; painful; Classifiers: 个 | |
| 艰苦HSK 5 | jiān kǔ | difficult; hard; arduous | |
| 辛苦HSK 4 | xīn kǔ | exhausting; hard; tough; arduous; to work hard; to go to a lot of trouble; hardship(s) | |
| 刻苦HSK 5 | kè kǔ | hardworking; assiduous | |
| 苦难HSK 4 | kǔ nàn | suffering |
| 1 | Teacher, you have worked hard. | |
| 2 | This cucumber is a little bitter. | |
| 3 | This tea has a bitter and astringent taste. | |
| 4 | You’ve worked hard, why not have a cup of tea? | |
| 5 | Love can sometimes bring pain to people. |