حروف اضافه زمان Prepositions رو كجا استفاده كنيم؟

:at
زمان روز (.at 8:00 a.m)
ظهر/شب/نيمه شب (at midnight)
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:in
قسمت هايي از روز (in the morning/evening/afternoon)
ماه (in July)
فصل (in the fall)
سال (in 1991)
دهه (in the 1990s)
قرن (in the nineteenth century)
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:on
روزهاي هفته (on Monday)
تاريخها (on March 20)
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:for/since
طول دوره زماني (for three days)
نقطه اي از مان (since August 19)
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:from...to
زمان آغاز ..... زمان پايان (.from 9 a.m. to 2 p.m)
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