help my friend with diffrent structures of tenses

[teelewis]

can someone please explain the difference in structure and usage between these tenses I have a friend who is a low level student and I cant explaine it probely to her please also Illustrate these with example sentences so she can understand it better.

a) Past simple and past continuous

b) Past simple and present perfect

c) Present perfect and past perfect

[Mister Micawber]

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Did you look HERE, for instance?
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