take tear cut
There was nothing furtive in what I did, I knew my parents would see   what  I'd done, and I didn't think there
was any  harm  in it.They always let me   [MASK]  the corners
after they'd opened them.Why should I think there was any harm in doing it first,  bearing   in mind that they weren't on hand to be   consulted  .Wouldn't they rather be left to doze in their summer deckchairs?