open

open and opened

We normally use open, not opened, as an adjective.

• I can read you like an open book. (not … an opened book.)
• Are the banks open this afternoon? (not Are the banks opened …?)

Opened is used as the past tense and past participle of the verb open, to talk about the action of opening.

• She opened her eyes and sat up.
• The safe was opened with dynamite.

When open is not used

Note that open is not the normal word to refer to the fastenings of clothes, or to switches or taps.

• I can’t untie/undo this shoelace. (not I can’t open this shoelace.)
• How do you unfasten this belt?
• Could you turn/switch the radio on? (not … open the radio?)
• Who left the taps turned on? (not Who left the taps open?)

note

For closed and shut, (see here).