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