can stale
Regular verb: stale - staled- staled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can stale
you can stale
he can stale
we can stale
you can stale
they can stale 	I can be staling
you can be staling
he can be staling
we can be staling
you can be staling
they can be staling	I can have staled
you can have staled
he can have staled
we can have staled
you can have staled
they can have staled	I can have been staling
you can have been staling
he can have been staling
we can have been staling
you can have been staling
they can have been staling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't stale
you can't stale
he can't stale
we can't stale
you can't stale
they can't stale 	I can't be staling
you can't be staling
he can't be staling
we can't be staling
you can't be staling
they can't be staling	I can't have staled
you can't have staled
he can't have staled
we can't have staled
you can't have staled
they can't have staled	I can't have been staling
you can't have been staling
he can't have been staling
we can't have been staling
you can't have been staling
they can't have been staling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I stale?
can you stale?
can he stale?
can we stale?
can you stale?
can they stale? 	can I be staling?
can you be staling?
can he be staling?
can we be staling?
can you be staling?
can they be staling? 	can I have staled?
can you have staled?
can he have staled?
can we have staled?
can you have staled?
can they have staled? 	can I have been staling?
can you have been staling?
can he have been staling?
can we have been staling?
can you have been staling?
can they have been staling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I stale?
can't you stale?
can't he stale?
can't we stale?
can't you stale?
can't they stale? 	can't I be staling?
can't you be staling?
can't he be staling?
can't we be staling?
can't you be staling?
can't they be staling? 	can't I have staled?
can't you have staled?
can't he have staled?
can't we have staled?
can't you have staled?
can't they have staled? 	can't I have been staling?
can't you have been staling?
can't he have been staling?
can't we have been staling?
can't you have been staling?
can't they have been staling?