将象限添加到R散点图中，并将线指向它们各自的标签

With ggplot2, can I add four quadrants. Basically just a line down the middle for the y and x axis (a plus sign)? I also wanted to see if i can have a lines pointing from the labels to their respective dots. The labeling overlap is getting problematic.With ggplot2, can I add four quadrants. Basical