I could expel you could expel he could expel we could expel you could expel they could expel
V-ing form
I could be expelling you could be expelling he could be expelling we could be expelling you could be expelling they could be expelling
Perfect
I could have expelled you could have expelled he could have expelled we could have expelled you could have expelled they could have expelled
V-ing perfect
I could have been expelling you could have been expelling he could have been expelling we could have been expelling you could have been expelling they could have been expelling
Negation
Simple form
I couldn't expel you couldn't expel he couldn't expel we couldn't expel you couldn't expel they couldn't expel
V-ing form
I couldn't be expelling you couldn't be expelling he couldn't be expelling we couldn't be expelling you couldn't be expelling they couldn't be expelling
Perfect
I couldn't have expelled you couldn't have expelled he couldn't have expelled we couldn't have expelled you couldn't have expelled they couldn't have expelled
V-ing perfect
I couldn't have been expelling you couldn't have been expelling he couldn't have been expelling we couldn't have been expelling you couldn't have been expelling they couldn't have been expelling
Interrogative form
Simple form
could I expel? could you expel? could he expel? could we expel? could you expel? could they expel?
V-ing form
could I be expelling? could you be expelling? could he be expelling? could we be expelling? could you be expelling? could they be expelling?
Perfect
could I have expelled? could you have expelled? could he have expelled? could we have expelled? could you have expelled? could they have expelled?
V-ing perfect
could I have been expelling? could you have been expelling? could he have been expelling? could we have been expelling? could you have been expelling? could they have been expelling?
Interro-negative form
Simple form
couldn't I expel? couldn't you expel? couldn't he expel? couldn't we expel? couldn't you expel? couldn't they expel?
V-ing form
couldn't I be expelling? couldn't you be expelling? couldn't he be expelling? couldn't we be expelling? couldn't you be expelling? couldn't they be expelling?
Perfect
couldn't I have expelled? couldn't you have expelled? couldn't he have expelled? couldn't we have expelled? couldn't you have expelled? couldn't they have expelled?
V-ing perfect
couldn't I have been expelling? couldn't you have been expelling? couldn't he have been expelling? couldn't we have been expelling? couldn't you have been expelling? couldn't they have been expelling?