\begin{Schunk}
\begin{Sinput}
 plot(salary~age , data=mydf, type="n", xlab="Age (years)", ylab="Hourly Wage (US)")
 ##with(mydf, text(age, salary, labels = mydf$sex)) ## same as:
 text(salary ~ age, data = mydf, labels = mydf$sex)
\end{Sinput}
\end{Schunk}
