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