I can thicken you can thicken he can thicken we can thicken you can thicken they can thicken
V-ing form
I can be thickening you can be thickening he can be thickening we can be thickening you can be thickening they can be thickening
Perfect
I can have thickened you can have thickened he can have thickened we can have thickened you can have thickened they can have thickened
V-ing perfect
I can have been thickening you can have been thickening he can have been thickening we can have been thickening you can have been thickening they can have been thickening
Negation
Simple form
I can't thicken you can't thicken he can't thicken we can't thicken you can't thicken they can't thicken
V-ing form
I can't be thickening you can't be thickening he can't be thickening we can't be thickening you can't be thickening they can't be thickening
Perfect
I can't have thickened you can't have thickened he can't have thickened we can't have thickened you can't have thickened they can't have thickened
V-ing perfect
I can't have been thickening you can't have been thickening he can't have been thickening we can't have been thickening you can't have been thickening they can't have been thickening
Interrogative form
Simple form
can I thicken? can you thicken? can he thicken? can we thicken? can you thicken? can they thicken?
V-ing form
can I be thickening? can you be thickening? can he be thickening? can we be thickening? can you be thickening? can they be thickening?
Perfect
can I have thickened? can you have thickened? can he have thickened? can we have thickened? can you have thickened? can they have thickened?
V-ing perfect
can I have been thickening? can you have been thickening? can he have been thickening? can we have been thickening? can you have been thickening? can they have been thickening?
Interro-negative form
Simple form
can't I thicken? can't you thicken? can't he thicken? can't we thicken? can't you thicken? can't they thicken?
V-ing form
can't I be thickening? can't you be thickening? can't he be thickening? can't we be thickening? can't you be thickening? can't they be thickening?
Perfect
can't I have thickened? can't you have thickened? can't he have thickened? can't we have thickened? can't you have thickened? can't they have thickened?
V-ing perfect
can't I have been thickening? can't you have been thickening? can't he have been thickening? can't we have been thickening? can't you have been thickening? can't they have been thickening?