I could bacterize you could bacterize she could bacterize we could bacterize you could bacterize they could bacterize
V-ing form
I could be bacterizing you could be bacterizing she could be bacterizing we could be bacterizing you could be bacterizing they could be bacterizing
Perfect
I could have bacterized you could have bacterized she could have bacterized we could have bacterized you could have bacterized they could have bacterized
V-ing perfect
I could have been bacterizing you could have been bacterizing she could have been bacterizing we could have been bacterizing you could have been bacterizing they could have been bacterizing
Negation
Simple form
I couldn't bacterize you couldn't bacterize she couldn't bacterize we couldn't bacterize you couldn't bacterize they couldn't bacterize
V-ing form
I couldn't be bacterizing you couldn't be bacterizing she couldn't be bacterizing we couldn't be bacterizing you couldn't be bacterizing they couldn't be bacterizing
Perfect
I couldn't have bacterized you couldn't have bacterized she couldn't have bacterized we couldn't have bacterized you couldn't have bacterized they couldn't have bacterized
V-ing perfect
I couldn't have been bacterizing you couldn't have been bacterizing she couldn't have been bacterizing we couldn't have been bacterizing you couldn't have been bacterizing they couldn't have been bacterizing
Interrogative form
Simple form
could I bacterize? could you bacterize? could she bacterize? could we bacterize? could you bacterize? could they bacterize?
V-ing form
could I be bacterizing? could you be bacterizing? could she be bacterizing? could we be bacterizing? could you be bacterizing? could they be bacterizing?
Perfect
could I have bacterized? could you have bacterized? could she have bacterized? could we have bacterized? could you have bacterized? could they have bacterized?
V-ing perfect
could I have been bacterizing? could you have been bacterizing? could she have been bacterizing? could we have been bacterizing? could you have been bacterizing? could they have been bacterizing?
Interro-negative form
Simple form
couldn't I bacterize? couldn't you bacterize? couldn't she bacterize? couldn't we bacterize? couldn't you bacterize? couldn't they bacterize?
V-ing form
couldn't I be bacterizing? couldn't you be bacterizing? couldn't she be bacterizing? couldn't we be bacterizing? couldn't you be bacterizing? couldn't they be bacterizing?
Perfect
couldn't I have bacterized? couldn't you have bacterized? couldn't she have bacterized? couldn't we have bacterized? couldn't you have bacterized? couldn't they have bacterized?
V-ing perfect
couldn't I have been bacterizing? couldn't you have been bacterizing? couldn't she have been bacterizing? couldn't we have been bacterizing? couldn't you have been bacterizing? couldn't they have been bacterizing?