Thank you all very much.
I generally use both "stay home" and "stayed at home", but the first one is the one I use more often. In the course of my life, I have talked both to Britishers and to Americans and I think I have been influenced by both groups.
As for the comme, I think in certain cases it does change the meaning:
a-At the party they sang as in the fifties.=in that style; in that manner
b-At the party they sang, as in the fifties.=maybe they sang in a different style but the important thing is that they sang and that was what was done in the fifties.
But when negation comes in, then things become more complicated!
a1-At the party they did not sing as in the fifties.=they did sing, but in a different manner/ or did they not sing at all?
b1-At the party they did not sing, as in the fifties.=this sounds to me as if in the fifties they did not sing and they did not sing at the party either.
What do you think?
Gratefully,
Navi.