Effortful activity directed towards a goal.

लंबी मेहनत

English Usage: Her hard work paid off when she finished the project ahead of time.

Hindi Usage: जब उसने प्रोजेक्ट समय से पहले पूरा किया, तो उसकी लंबी मेहनत का फल मिला।

To engage in difficult or demanding tasks that require effort.

कठोर कार्य करना

English Usage: They had to hard work to complete the assignment on time.

Hindi Usage: उन्हें असाइनमेंट समय पर पूरा करने के लिए कठोर कार्य करना पड़ा।