\starttext

    x\high{high}
    x\low {low}
    x\hilo{high}{low}
    x\lohi{low}{high}

    \def\highvfraction   {0.1}
    \def\lowvfraction    {0.1}
    \def\highlowvfraction{0.2}
    \def\highlowhfraction{0.2}

    x\high{high}
    x\low {low}
    x\hilo{high}{low}
    x\lohi{low}{high}

\stoptext
