about english question

正確: I have(not has) finished my work.
was + ___ed (past tense) = 被動式
example: I was scolded by my mother. 我被我母親責罵.
has/had not 後面跟隨的verb is using 過去分詞~ example: She has not been to London since 1998.
is not/was not 後面跟隨的verb is using 現在式 ~ example: I was not doing it wrong.

I was finished my work 正確
如果要用"has" 正確的是I HAVE finished my work. 因為"I"是1st person singular.
eg. I was finished my work/I have finished my work. Was finished=past tense. Have finished=past perfect. 分別就在用法。用was的話，不能單獨一句，一定要有另一句來support它。eg. I was finished my work so I went to the park. 但你可以只說I have finished my work. (如果你只說I was finished my work, 這不表達一個"complete idea")

Has not: verb=past tense. (she has not finished her work yet)
Had not: verb=present. (she had not finish her work)
is not: verb=verb+ing (She is not coming)
was not: verb=verb+ing + infinitive (She was not going to come)