Regular verb: stiffen - stiffened - stiffened
Simple form | V-ing form |
I can stiffen you can stiffen she can stiffen we can stiffen you can stiffen they can stiffen | I can be stiffening you can be stiffening she can be stiffening we can be stiffening you can be stiffening they can be stiffening |
Perfect | V-ing perfect |
I can have stiffened you can have stiffened she can have stiffened we can have stiffened you can have stiffened they can have stiffened | I can have been stiffening you can have been stiffening she can have been stiffening we can have been stiffening you can have been stiffening they can have been stiffening |
Simple form | V-ing form |
I cannot stiffen you cannot stiffen she cannot stiffen we cannot stiffen you cannot stiffen they cannot stiffen | I cannot be stiffening you cannot be stiffening she cannot be stiffening we cannot be stiffening you cannot be stiffening they cannot be stiffening |
Perfect | V-ing perfect |
I cannot have stiffened you cannot have stiffened she cannot have stiffened we cannot have stiffened you cannot have stiffened they cannot have stiffened | I cannot have been stiffening you cannot have been stiffening she cannot have been stiffening we cannot have been stiffening you cannot have been stiffening they cannot have been stiffening |
Simple form | V-ing form |
can I stiffen? can you stiffen? can she stiffen? can we stiffen? can you stiffen? can they stiffen? | can I be stiffening? can you be stiffening? can she be stiffening? can we be stiffening? can you be stiffening? can they be stiffening? |
Perfect | V-ing perfect |
can I have stiffened? can you have stiffened? can she have stiffened? can we have stiffened? can you have stiffened? can they have stiffened? | can I have been stiffening? can you have been stiffening? can she have been stiffening? can we have been stiffening? can you have been stiffening? can they have been stiffening? |
Simple form | V-ing form |
can I not stiffen? can you not stiffen? can she not stiffen? can we not stiffen? can you not stiffen? can they not stiffen? | can I not be stiffening? can you not be stiffening? can she not be stiffening? can we not be stiffening? can you not be stiffening? can they not be stiffening? |
Perfect | V-ing perfect |
can I not have stiffened? can you not have stiffened? can she not have stiffened? can we not have stiffened? can you not have stiffened? can they not have stiffened? | can I not have been stiffening? can you not have been stiffening? can she not have been stiffening? can we not have been stiffening? can you not have been stiffening? can they not have been stiffening? |