can tree
Regular verb: tree - treed- treed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can tree
you can tree
she can tree
we can tree
you can tree
they can tree 	I can be treeing
you can be treeing
she can be treeing
we can be treeing
you can be treeing
they can be treeing	I can have treed
you can have treed
she can have treed
we can have treed
you can have treed
they can have treed	I can have been treeing
you can have been treeing
she can have been treeing
we can have been treeing
you can have been treeing
they can have been treeing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't tree
you can't tree
she can't tree
we can't tree
you can't tree
they can't tree 	I can't be treeing
you can't be treeing
she can't be treeing
we can't be treeing
you can't be treeing
they can't be treeing	I can't have treed
you can't have treed
she can't have treed
we can't have treed
you can't have treed
they can't have treed	I can't have been treeing
you can't have been treeing
she can't have been treeing
we can't have been treeing
you can't have been treeing
they can't have been treeing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I tree?
can you tree?
can she tree?
can we tree?
can you tree?
can they tree? 	can I be treeing?
can you be treeing?
can she be treeing?
can we be treeing?
can you be treeing?
can they be treeing? 	can I have treed?
can you have treed?
can she have treed?
can we have treed?
can you have treed?
can they have treed? 	can I have been treeing?
can you have been treeing?
can she have been treeing?
can we have been treeing?
can you have been treeing?
can they have been treeing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I tree?
can't you tree?
can't she tree?
can't we tree?
can't you tree?
can't they tree? 	can't I be treeing?
can't you be treeing?
can't she be treeing?
can't we be treeing?
can't you be treeing?
can't they be treeing? 	can't I have treed?
can't you have treed?
can't she have treed?
can't we have treed?
can't you have treed?
can't they have treed? 	can't I have been treeing?
can't you have been treeing?
can't she have been treeing?
can't we have been treeing?
can't you have been treeing?
can't they have been treeing?