Pay already on dd-mm-yy 語法對嗎

Pay already on dd-mm-yy 語法對嗎?
already(剛剛) - 需要present perfect tense
I have already paid on 01-01-2008. (present perfect tense)
I paid on on 01-01-2008. (past tense)

Pay 不是應該用 Paid 嗎 ?
Pay 的過去年及過去分詞係Paid.
視乎你用什麼時式表達
I will pay on .....
I hav already paid on .....
I paid om.....

Pay- Paid才對 already on - 如要使用[on] Monday, Tuesday...才對
Paid already on Monday.
假使要用日期 - Payment already make as at 年月日

I have already paid since 1/1/2008

or I paid on 1/1/2008