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