How can I shade the regions under the curve in R studio? This is my code:

x=seq(from=-4,to=4,length.out=50) y <- dt(x, df = 19) plot(x, y,type="l")

qt(c(.025, .975), df=19)

I have created a t-distribution and now I want shade the region under the curve from -4 to -2.093024 and from 2.093024 to 4. How can I do that in R studio?