class _verb_canonical 
{
    <: verb;
    %% ensure no extraction on verb args
    desc.@extracted0 = value(-);
    desc.@extracted1 = value(-);
    desc.@extracted2 = value(-);
    desc.extraction = node(S).top.extraction;
    %%    node(S).bot.extraction = node(S).top.extraction;
    %% By default, no extraction
    %% S + node(S).bot.extraction == value(-);
    node(S).bot.extraction = value(-|adjx);
    node(S).bot.xarg.case = value(-);
}