1. He should have thought more carefully.
2. He regrets that he didn't think more carefully.
3. I regret that he didn't think more carefully.
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Does #1 mean #2 or #3?
4 answers
#1 means #2
Aghedo is right. Do you see why #3 doesn't mean the same as either of the others?
4. You should have come earlier.
5. I'm sorry you didn't come earlier.
(Doesn't #4 mean #5?)
5. I'm sorry you didn't come earlier.
(Doesn't #4 mean #5?)
4 and 5 are similar in meaning, but not identical.