해야 함
Used to indicate obligation, duty, or advice.
예문:
"You should wear a helmet while riding a bike."
"Students should submit their assignments by Friday."
할 것임
Used to indicate what is probable or expected.
예문:
"The movie should be finished by ten o'clock."
"The price should be around twenty dollars."
했어야 함
Used with a past participle to express regret about a past action.
예문:
"I should have apologized to her yesterday."
"We should have taken the shorter route."
만약 상황
Used in formal conditions to express a possibility.
예문:
"Should you encounter any errors, restart the system."
"If he should call, tell him I am busy."
의외 상황
Used to express surprise, disbelief, or strong emotion.
예문:
"It is strange that she should leave without saying goodbye."
"Why should I believe anything you say?"
완곡 표현
Used in the first person to express a polite or tentative opinion.
예문:
"I should think that this color suits you better."
"I should imagine the view is beautiful there."
당위성
Used in 'that' clauses after verbs of suggesting or demanding.
예문:
"The doctor recommended that he should rest."
"It is necessary that every member should vote."