Opened is the past tense of open.
The simple past tense of the word "open" is "opened."
"opened fire" is the past tense.
The past tense for open is opened.
past
The past tense and past participle of open is opened.
The past perfect tense of open is 'had opened'.
The present perfect tense of open is:I/You/We/They have opened.He/She/It has opened.
Present perfect is formed this way - have/has + past participle. (not past tense)Singular subjectsThe hospital has opened a new wing - opened is past participle of openShe has written to him - written is the past participle of writePlural subjectsThey have seen the movie. - seen is the past participle of see.The boys have talked all night - talk is past participle of talk
you opened the door
No... that is called a weak verb.
the past tense of am is was and the past tense of has is had
No because one verb is past tense and the other is present tense. You should say "Yes, this sample has been opened and processed."