Student or Learner
1) I will be washing the car if you visit me at 5 tomorrow. (Future Progressive)
2) I have been washing the car since 5. (Present Perfect Progressive)
3) I had been washing the car at 4 when you visited me at 5.(Past Perfect Progressive)
4) I will have been washing the car at 3 if you come to visit me at 4. (Fiture Perfect Progressive)
3- since 4
4- since 3
Sentences 3&4 sound more like examples than real sentnces, though.