Last night, I bought "Cambridge English Grammar Today" (by Ronald Carter, Michael McVarthy, Geraldine Mark and Anne O'Keeffe).
I found the following at pages 277-278 of the said book:
"We use 'see', not 'watch', when we talk about being at sports matches or public performances, such as films, theatre and dramas. However, we 'watch' the television:
1. We saw a wonderful new film last night. You'll have to go and see it while it's in the cinema.
Not: [strike]We watched...You'll have to go and watch...[/strike]
2. I watched 'Phantom of the Opera' last night on DVD. ------[I was at home.]
3. I saw 'Phantom of the Opera' last night-----[I was at a theatre or cinema.]
You would have to forgive me---is this some recent usage? (Well, this is not I have learnt at school---all along I have been under the impression that in all cases of "movies", "plays" and "films", etc., and those that require one to focus, one "watches" and not "sees".)
Could someone help me?