can mark
Verbo regular: mark - marked- marked

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I can mark
you can mark
he can mark
we can mark
you can mark
they can mark 	I can be marking
you can be marking
he can be marking
we can be marking
you can be marking
they can be marking	I can have marked
you can have marked
he can have marked
we can have marked
you can have marked
they can have marked	I can have been marking
you can have been marking
he can have been marking
we can have been marking
you can have been marking
they can have been marking	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I can't mark
you can't mark
he can't mark
we can't mark
you can't mark
they can't mark 	I can't be marking
you can't be marking
he can't be marking
we can't be marking
you can't be marking
they can't be marking	I can't have marked
you can't have marked
he can't have marked
we can't have marked
you can't have marked
they can't have marked	I can't have been marking
you can't have been marking
he can't have been marking
we can't have been marking
you can't have been marking
they can't have been marking	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can I mark?
can you mark?
can he mark?
can we mark?
can you mark?
can they mark? 	can I be marking?
can you be marking?
can he be marking?
can we be marking?
can you be marking?
can they be marking? 	can I have marked?
can you have marked?
can he have marked?
can we have marked?
can you have marked?
can they have marked? 	can I have been marking?
can you have been marking?
can he have been marking?
can we have been marking?
can you have been marking?
can they have been marking? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
can't I mark?
can't you mark?
can't he mark?
can't we mark?
can't you mark?
can't they mark? 	can't I be marking?
can't you be marking?
can't he be marking?
can't we be marking?
can't you be marking?
can't they be marking? 	can't I have marked?
can't you have marked?
can't he have marked?
can't we have marked?
can't you have marked?
can't they have marked? 	can't I have been marking?
can't you have been marking?
can't he have been marking?
can't we have been marking?
can't you have been marking?
can't they have been marking?