I was watching the television, when suddenly the lights went out.

[sitifan]

I was watching the television, when suddenly the lights went out. (My bold.)
Source: Randolph Quirk, Sidney Greenbaum, Geoffrey Leech, and Jan Svartvik, A Comprehensive Grammar of the English Language, p1084.

Is the expression "watching the television" acceptable?

 

[dunchee]

Yes.

 

[Tarheel]

I was watching TV when the lights went out.

That's more likely.

 

[sitifan]

Are all the expressions below acceptable to native speakers?
1. watch the television
2. watch television
3. watch the TV
4 watch TV

 

[emsr2d2]

They're all grammatical but "watch TV" is the most common, in BrE at least.