“Should have” is a modal phrase in English that is often used to express regret or criticism concerning past actions. When using “should have,” it indicates that something was expected or recommended to be done in the past, but it was not carried out. This can convey a sense of missed opportunities or a reflection on past choices.

For example, if someone forgets to study for an exam and subsequently performs poorly, they might say, “I should have studied more,” indicating regret for not taking the recommended action of studying.

In a similar vein, if a person misses a deadline for a project due to procrastination, they could acknowledge, “I should have started earlier,” highlighting the realization that an earlier start was the expected or recommended course of action that was not followed.

Overall, when “should have” is used in a sentence, it serves as a way to express hindsight, acknowledging what could or should have been done differently in the past to potentially improve an outcome or avoid a mistake.