plot(E~G1, type="l",pch=6, data=na.omit(data.frame(G1,E)),xlim=c(0,4),ylim=c(3500, 6100), xaxs="i", yaxs="i",lty=3,lwd=3,col="red")

lines(E~G2, type="l", data=na.omit(data.frame(G2,E)),lty=2,lwd=3,col="green" )
lines(E~G3, type="l", data=na.omit(data.frame(G3,E)),lty=1,lwd=3,col="grey" )`lines(E~G4, type="l", data=na.omit(data.frame(G4,E)),lty=4,lwd=3,col="black" )`