can undertain
Regular verb: undertain - undertained- undertained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can undertain
you can undertain
he can undertain
we can undertain
you can undertain
they can undertain 	I can be undertaining
you can be undertaining
he can be undertaining
we can be undertaining
you can be undertaining
they can be undertaining	I can have undertained
you can have undertained
he can have undertained
we can have undertained
you can have undertained
they can have undertained	I can have been undertaining
you can have been undertaining
he can have been undertaining
we can have been undertaining
you can have been undertaining
they can have been undertaining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot undertain
you cannot undertain
he cannot undertain
we cannot undertain
you cannot undertain
they cannot undertain 	I cannot be undertaining
you cannot be undertaining
he cannot be undertaining
we cannot be undertaining
you cannot be undertaining
they cannot be undertaining	I cannot have undertained
you cannot have undertained
he cannot have undertained
we cannot have undertained
you cannot have undertained
they cannot have undertained	I cannot have been undertaining
you cannot have been undertaining
he cannot have been undertaining
we cannot have been undertaining
you cannot have been undertaining
they cannot have been undertaining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I undertain?
can you undertain?
can he undertain?
can we undertain?
can you undertain?
can they undertain? 	can I be undertaining?
can you be undertaining?
can he be undertaining?
can we be undertaining?
can you be undertaining?
can they be undertaining? 	can I have undertained?
can you have undertained?
can he have undertained?
can we have undertained?
can you have undertained?
can they have undertained? 	can I have been undertaining?
can you have been undertaining?
can he have been undertaining?
can we have been undertaining?
can you have been undertaining?
can they have been undertaining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not undertain?
can you not undertain?
can he not undertain?
can we not undertain?
can you not undertain?
can they not undertain? 	can I not be undertaining?
can you not be undertaining?
can he not be undertaining?
can we not be undertaining?
can you not be undertaining?
can they not be undertaining? 	can I not have undertained?
can you not have undertained?
can he not have undertained?
can we not have undertained?
can you not have undertained?
can they not have undertained? 	can I not have been undertaining?
can you not have been undertaining?
can he not have been undertaining?
can we not have been undertaining?
can you not have been undertaining?
can they not have been undertaining?