请各位告诉我draw语句怎么用，老师教我们时没有仔细说过

SyntaxDRAW [target,] cmds$DescriptionStatement for sequenced pixel plotting. Drawing will take place onto the current work page set via SCREENSET or onto the target GET/PUT buffer if specified.The DRAW statement can be used to issue several drawing commands all at once; it is useful to quickly draw figures. The command string accepts the following commands:Commands to plot pixels:Command Description Commands to plot pixels: B Optional prefix: move but do not draw. N Optional prefix: draw but do not move. Mx,y Move to specified screen location. if + or - precedes x, movement is relative to current cursor position. U[n] Move n units up. If n is omitted, 1 is assumed. D[n] Move n units down. If n is omitted, 1 is assumed. L[n] Move n units left. If n is omitted, 1 is assumed. R[n] Move n units right. If n is omitted, 1 is assumed. E[n] Move n units up and right. If n is omitted, 1 is assumed. F[n] Move n units down and right. If n is omitted, 1 is assumed. G[n] Move n units down and left. If n is omitted, 1 is assumed. H[n] Move n units up and left. If n is omitted, 1 is assumed. Commands to color: Cn Changes current foreground color to n. Pp,b Flood fills region with border color b with color p. Commands to scale and rotate: Sn Sets the current unit length, default is 4 pixels perunit. An Rotate n*90 degrees (n ranges 0-3). TAn Rotate n degrees (n ranges 0-359) Extra commands: Xp Executes commands at address p.