English verb conjugation
CAN PIERCE

Regular verb: pierce - pierced - pierced

Affirmation

Simple form	V-ing form
I can pierce you can pierce he can pierce we can pierce you can pierce they can pierce	I can be piercing you can be piercing he can be piercing we can be piercing you can be piercing they can be piercing
Perfect	V-ing perfect
I can have pierced you can have pierced he can have pierced we can have pierced you can have pierced they can have pierced	I can have been piercing you can have been piercing he can have been piercing we can have been piercing you can have been piercing they can have been piercing

Negation

Simple form	V-ing form
I can't pierce you can't pierce he can't pierce we can't pierce you can't pierce they can't pierce	I can't be piercing you can't be piercing he can't be piercing we can't be piercing you can't be piercing they can't be piercing
Perfect	V-ing perfect
I can't have pierced you can't have pierced he can't have pierced we can't have pierced you can't have pierced they can't have pierced	I can't have been piercing you can't have been piercing he can't have been piercing we can't have been piercing you can't have been piercing they can't have been piercing

Interrogative form

Simple form	V-ing form
can I pierce? can you pierce? can he pierce? can we pierce? can you pierce? can they pierce?	can I be piercing? can you be piercing? can he be piercing? can we be piercing? can you be piercing? can they be piercing?
Perfect	V-ing perfect
can I have pierced? can you have pierced? can he have pierced? can we have pierced? can you have pierced? can they have pierced?	can I have been piercing? can you have been piercing? can he have been piercing? can we have been piercing? can you have been piercing? can they have been piercing?

Interro-negative form

Simple form	V-ing form
can't I pierce? can't you pierce? can't he pierce? can't we pierce? can't you pierce? can't they pierce?	can't I be piercing? can't you be piercing? can't he be piercing? can't we be piercing? can't you be piercing? can't they be piercing?
Perfect	V-ing perfect
can't I have pierced? can't you have pierced? can't he have pierced? can't we have pierced? can't you have pierced? can't they have pierced?	can't I have been piercing? can't you have been piercing? can't he have been piercing? can't we have been piercing? can't you have been piercing? can't they have been piercing?