如何在R中的绘图区域外绘制线条或添加文本？

Thank you for reading. I find that I am unable to draw lines/points or add text outside of the plot area. If I draw a line from inside the plot (within the axis) area to the area of the xlab main title areas only the part within the plot shows. In a multiple plot graph (mfrow) the line/point will only be drawn inside the last active plot.Thank you for reading. I find that I am unable