. #delimit ;
delimiter now ;
. tw(connected defect cdf n,msymbol(square) )
> xlabel(1"Engine"2"Electrical System"3"Brakes"4"Air Conditioning"5"Transmission"6"Body Integrity"))
> ytitle(Percentaeg of Defects Observed)
> xtitle(off)
> clpattern(solid dash)
> text(85 5.5 Cumulative)
> text(10 5.5 Indvidual)
> legend(off) ) ;
) required
r(100);

求问什么是“）required ”