I am sorry then. But expertboxing is not very trustworthy. I can name 3-4 examples when good coaches like Kenny Weldon or Teddy Atlas not do the technique properly themselves, but they still can explain it properly with the words. This is why better see real examples of top fighters.
hear we go ,,I'm Gunnar put a cat among the pigeons,,,the examples are simply a straight right to me a right cross is when your straight right go's over the top of there jab ,,slip the jab or take the Punch & the straight crosses over the jab ,,it's pretty much the some motion but after the hip turn let the elbow move away from the body when turning the knuckles over