Open or opened?

We use open as an adjective to mean ‘not closed’:

• I stopped the car when I realised that the door was open.
• Not: … that the door was opened.

Opened is the past form of the verb open:

• Can you open the window, please? (present)
• She opened her eyes and immediately looked at the clock. (past)

warning

We don’t use open to refer to turning on taps and switches:

• Please turn on the taps separately.
• Not: Please open the taps …
• Can you switch on the lights, please?
• Not: Can you open the lights …