Student or Learner
The shop was opened from 8 a.m. to 11 p.m. yesterday.
The shop was open from 8 a.m.to 11 p.m.yesterday.
I think the second sentence is correct.
The shop is opened from 9 a.m. to 10 p.m. every day.
The shop is open from 9 a.m. to 10 p.m.every day.
I think the second sentence is right.
The shop was opened at 9 a.m. this morning.
The shop was open at 9 a.m. this morning.
I think the first sentence is right.
Am I right? Whether I am right or wrong, I don't know why.
Please help me~!
Your choices are correct for usual usage, but the others are possible, especially 3B-- the third sets depends particularly on whether we are speaking of the action (opened) or the condition (open).
The confusion arises in part because of its inconsistency with the opposite, closed. Open is the adjective, so that opened serves clearly as the participle, but closed serves as both:
The store was opened by the clerk at 9 am.
The store was closed by the clerk at 5 pm.
The store was open from 9 to 5.
The store was closed from 5 to 9.