Open the light / close the light
Open the light
Switch on the light (and 'close the light' = switch it off).
It's getting dark, Kabir. Open the light, please.
Switch on / turn on the light
Make the light start working; 'switch off' stops it.
It's getting dark, Kabir. Switch on the light, please.
Remember: Heard in parts of India, alongside 'on the light' and 'close the fan'. Clear in India; outside India 'open' suggests a door or box. Say 'switch on' and 'switch off'.