I could arrive you could arrive she could arrive we could arrive you could arrive they could arrive
V-ing form
I could be arriving you could be arriving she could be arriving we could be arriving you could be arriving they could be arriving
Perfect
I could have arrived you could have arrived she could have arrived we could have arrived you could have arrived they could have arrived
V-ing perfect
I could have been arriving you could have been arriving she could have been arriving we could have been arriving you could have been arriving they could have been arriving
Negation
Simple form
I could not arrive you could not arrive she could not arrive we could not arrive you could not arrive they could not arrive
V-ing form
I could not be arriving you could not be arriving she could not be arriving we could not be arriving you could not be arriving they could not be arriving
Perfect
I could not have arrived you could not have arrived she could not have arrived we could not have arrived you could not have arrived they could not have arrived
V-ing perfect
I could not have been arriving you could not have been arriving she could not have been arriving we could not have been arriving you could not have been arriving they could not have been arriving
Interrogative form
Simple form
could I arrive? could you arrive? could she arrive? could we arrive? could you arrive? could they arrive?
V-ing form
could I be arriving? could you be arriving? could she be arriving? could we be arriving? could you be arriving? could they be arriving?
Perfect
could I have arrived? could you have arrived? could she have arrived? could we have arrived? could you have arrived? could they have arrived?
V-ing perfect
could I have been arriving? could you have been arriving? could she have been arriving? could we have been arriving? could you have been arriving? could they have been arriving?
Interro-negative form
Simple form
could I not arrive? could you not arrive? could she not arrive? could we not arrive? could you not arrive? could they not arrive?
V-ing form
could I not be arriving? could you not be arriving? could she not be arriving? could we not be arriving? could you not be arriving? could they not be arriving?
Perfect
could I not have arrived? could you not have arrived? could she not have arrived? could we not have arrived? could you not have arrived? could they not have arrived?
V-ing perfect
could I not have been arriving? could you not have been arriving? could she not have been arriving? could we not have been arriving? could you not have been arriving? could they not have been arriving?