OPEN is used as an adjective:
- “The shop is open until 7.00.”
- “We don’t know who left the door open.”
We used OPENED as the past tense and past participle of the verb open, to talk about the action of opening.
- “They opened the door and entered the house.”
- “She opened her eyes and left the room.”
We cannot use OPEN when we refer to the fastening of clothes, or to switches or taps.
- “I can’t untie/undo the child’s shoelace.”
- “You should never unfasten your safety belt when driving.”
- “Could you switch /turn the TV on?
- “Your brother left the tap turned on.”