-해야죠 and -해야 하죠?
It is the difference between -아/어야지(요) and -아/어야 하지(요), where -야 하지 is just one of -아/어야지 use cases.
* -아/어야 하지 = V-아/어야 하다(should/must V) phrased like a reminder or soft opinion.
- 이런 일은 제가 해야 하죠/되죠? = This kind of things are my job.
* -아/어야지. = 1) same as 야 하지, 2) states one's intention or determination (like talking to oneself - so no 요 at the end), 2) suggests an action to the other person.
- 이런 일은 제가 해야죠 (=해야 하죠). (1)
- 연습 열심히 해서 달리기 일등해야지 (2)
= I think I'll practice hard and win the sprint.
- 힘드시면 좀 쉬었다 하시죠.(3)
= Why don't you take a break if you're tired?
The -지 ending is one of the most subtle ones, with even more variants than mentioned abobe.
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