kHAHESH MIKONAM
For making "subjunctive" you can't use be+infinitive...the formula is >>be+Present root+suffix
For example the verb"to buy"
Infinitive is "Kharidan"
Present root is "Khar"
subjunctive would be " be+khar+am/i/ad/im/id/and
That I buy=Ke bekharam
That you buy=Ke bekhari
That he/she buys=Ke bekharad__ke bekhare(informal)
That we buy=Ke bekharim
That you buy=Ke bekharid_____ke bekharin(informal)
That they buy=Ke bekharand_____ke bekharan(informal)
The reason that the endings( you mean the suffix??) are different is because these suffix refer to different subjects...If you look at the sentences I wrote in the first sentence :
1-I want her to come=Azash mikham ke biyad(subjunctive)
"biyad" means "that she comes!
in the second one :;2-I want to ask you=Mikham azat(az to) beporsam(subjunctive)
"am" in "beporsam" refers to "I">>>>
If for example our sentence was like this :
She wants to ask you>>>Oun mihad azat beporse/beporsad
The suffix are like this :(you gotta remember these!)
I=am >>>>>beporsam/beram/benevisam
You=i >>>beporsi/beri/benevisi
He/she=ad(formal)/e(informal) >>>beporsad(formal)/beporse(informal)
We=im >>>>beporsim/berim
You (plural)=id(formal)/in(informal but still it's polite) >>>beporsim/beporsin/berid/berin
They=and(formal)/an(informal) >>>beporsand/beporsan/beravand/beran