操劳 (cāo láo): 열심히 일하다.

Mom works hard at housework every day, busy from morning till night, without even time to sit down and have a cup of tea.

In order to pay for his children's education, he works hard away from home all year round and seldom returns.

Teacher Wang worked hard all his life; after retirement, he can finally rest well.

Looking at his wife's rough hands from hard work, his heart was filled with gratitude and guilt.

The nurses work hard day and night, carefully taking care of every patient; it's very tough.