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