past progressive

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ماضی استمراری

گذشته مجهول

ماضی استمراری میشود present perfect

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مثال:
I was studing when the power went out
I was'nt sleeping when the power went out
?Were you studing when the power went out
?What were you doing when thepower went out

گذشته استمراری یا گذشته پیشرفته
مثال:what were you doing yesterday at 8?

گذشته ی استمراری.