The second principle part of the verb ( The past tense ) is used to express past time. ( No auxiliary verb is used with this form.)
(Common auxiliary verbs - is,are,was,were,can,could,do,did,has,had,have,may,might,must,shall,should,will,would)
[B]We filled the order yesterday.[/B]
[B]She did what was expected of her.[/B]
[U]Do not use a past participle form to express the past tense.[/U]
He drank his coffee. ( [B]Not[/B]: He drunk his coffee.)
I saw it. ( [B]Not:[/B] I seen it. )
They began it together. ( [B]Not:[/B] They begun it together.)
He was the one who did it. ( [B]Not:[/B] He was the one who done it.)
To form the past perfect tense. This tense indicates action that was completed before another past action. It consists of the verb has plus the past participle.
[B]We had filled the orders before we saw your letter.
[B]She had done the job before we arrived.[/B]
If you find yourself in need of reference, check out a library and use a book called The Gregg Reference Manual.