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