There is a class of verbs in Persian which are stationary. That is to say, they govern an “action” in which there is no movement:

[tag resources stationaryverbs_01]نشستن[/tag]
nešastan
‘to sit’

[tag resources stationaryverbs_02]خوابیدن[/tag]
xābidan
‘to sleep, go to bed’

[tag resources stationaryverbs_03]ایستادن[/tag]
istādan
‘to stand’

The construction of the present progressive of these stationary verbs is derived from the participle. With the می prefix all of these verbs govern an action which is either in the process of taking place before becoming stationary, or is going to take place (as in the future tense). Compare the following sentences; also compare and contrast them with their English counterparts:

[tag resources stationaryverbs_04]من اینجا می نشینم[/tag]
man injā mi nešinam
“I am going to sit here.”

[tag resources stationaryverbs_05]من دارم اینجا می نشینم[/tag]
man dāram injā mi nešinam
“I am (in the process of) sitting (down) here.”

[tag resources stationaryverbs_06]او اینجا نشسته است[/tag]
u injā nešaste ast
“He/she is sitting here.”

[tag resources stationaryverbs_07]او نشسته است تا من برسم[/tag]
u nešaste ast tā man berasam
“He/she is sitting [there] (waiting for) me to arrive.” (literally, “until I arrive”)

[tag resources stationaryverbs_08]اینجا می نشینی تا آن ها بیایند؟[/tag]
injā mi nešini tā ān hā biyāyand?
“Are you going to sit here until they show up?” (literally, “come”)

[tag resources stationaryverbs_09]من دو ساعت است (که) اینجا نشسته ام[/tag]
man do sā’at ast (ke) injā nešaste am
“I have been sitting here for two hours.”

[tag resources stationaryverbs_10]من اینجا می خوابم[/tag]
man injā mi xābam
“I am going to sleep/lie down here.”

[tag resources stationaryverbs_11]من دارم اینجا می خوابم[/tag]
man dāram injā mi xābam
“I am (in the process of) sleeping (as in going to bed) here.”

[tag resources stationaryverbs_12]من دارم می خوابم[/tag]
man dāram mi xābam
“I am going to bed.”

[tag resources stationaryverbs_13]من اینجا خوابیده ام[/tag]
man injā xābide am
“I am sleeping/lying down here.”

[tag resources stationaryverbs_14]من خوابیده ام[/tag]
man injā xābide am
“I am sleeping/asleep.”

[tag resources stationaryverbs_15]من تا صبح همینجا می خوابم[/tag]
man tā sobh haminjā mi xābam
“I am going to sleep here until morning.”

[tag resources stationaryverbs_16]من سه روز است اینجا خوابیده ام[/tag]
man se ruz ast injā xābide am
“I have been sleeping here for three days.”

[tag resources stationaryverbs_17]من اینجا می ایستم[/tag]
man injā mi istam
“I am going to stand here.”

[tag resources stationaryverbs_18]من دارم می ایستم[/tag]
man dāram injā mi istam
“I am standing up.”

[tag resources stationaryverbs_19]من اینجا ایستاده ام[/tag]
man injā istāde am
“I am standing here.”

[tag resources stationaryverbs_20]من تا صبح همینجا می ایستم[/tag]
man tā sobh haminjā mi istam
“I am going to stand here until morning.”

[tag resources stationaryverbs_21]من از صبح اینجا ایستاده ام[/tag]
man az sobh injā istāde am
“I have been standing here since this morning.”

[tag resources stationaryverbs_22]من اینجا می افتم[/tag]
man injā mi oftam
“I am going to fall/crash here.”
(note semantic parallel between the word افتادن as ‘to crash’, both as slang in Persian and English)

[tag resources stationaryverbs_23]من دارم اینجا می افتم[/tag]
man dāram injā mi oftam
“I am (in the process of) falling/crashing here.”

[tag resources stationaryverbs_24]من اینجا افتاده ام[/tag]
man injā oftāde am
“I am lying down here.” (as in not moving)

[tag resources stationaryverbs_25]من از صبح اینجا افتاده ام[/tag]
man az sobh injā oftāde am
“I have been lying here since this morning, I have been lying down here since this morning.”

In the construction of the past progressive of these verbs, the present copulas are simply replaced with the past copulas:

[tag resources stationaryverbs_26]من اینجا نشسته ام[/tag]
man injā nešaste am
“I am sitting here.”

[tag resources stationaryverbs_27]من آنجا نشسته بودم[/tag]
man injā nešaste am
“I was sitting there.”

Note that من آنجا می نشستم man ānjā mi nešastam means “I used to sit there.”