can mast
Regular verb: mast - masted- masted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can mast
you can mast
he can mast
we can mast
you can mast
they can mast 	I can be masting
you can be masting
he can be masting
we can be masting
you can be masting
they can be masting	I can have masted
you can have masted
he can have masted
we can have masted
you can have masted
they can have masted	I can have been masting
you can have been masting
he can have been masting
we can have been masting
you can have been masting
they can have been masting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot mast
you cannot mast
he cannot mast
we cannot mast
you cannot mast
they cannot mast 	I cannot be masting
you cannot be masting
he cannot be masting
we cannot be masting
you cannot be masting
they cannot be masting	I cannot have masted
you cannot have masted
he cannot have masted
we cannot have masted
you cannot have masted
they cannot have masted	I cannot have been masting
you cannot have been masting
he cannot have been masting
we cannot have been masting
you cannot have been masting
they cannot have been masting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I mast?
can you mast?
can he mast?
can we mast?
can you mast?
can they mast? 	can I be masting?
can you be masting?
can he be masting?
can we be masting?
can you be masting?
can they be masting? 	can I have masted?
can you have masted?
can he have masted?
can we have masted?
can you have masted?
can they have masted? 	can I have been masting?
can you have been masting?
can he have been masting?
can we have been masting?
can you have been masting?
can they have been masting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not mast?
can you not mast?
can he not mast?
can we not mast?
can you not mast?
can they not mast? 	can I not be masting?
can you not be masting?
can he not be masting?
can we not be masting?
can you not be masting?
can they not be masting? 	can I not have masted?
can you not have masted?
can he not have masted?
can we not have masted?
can you not have masted?
can they not have masted? 	can I not have been masting?
can you not have been masting?
can he not have been masting?
can we not have been masting?
can you not have been masting?
can they not have been masting?