can suffix
Regular verb: suffix - suffixed- suffixed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can suffix
you can suffix
she can suffix
we can suffix
you can suffix
they can suffix 	I can be suffixing
you can be suffixing
she can be suffixing
we can be suffixing
you can be suffixing
they can be suffixing	I can have suffixed
you can have suffixed
she can have suffixed
we can have suffixed
you can have suffixed
they can have suffixed	I can have been suffixing
you can have been suffixing
she can have been suffixing
we can have been suffixing
you can have been suffixing
they can have been suffixing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot suffix
you cannot suffix
she cannot suffix
we cannot suffix
you cannot suffix
they cannot suffix 	I cannot be suffixing
you cannot be suffixing
she cannot be suffixing
we cannot be suffixing
you cannot be suffixing
they cannot be suffixing	I cannot have suffixed
you cannot have suffixed
she cannot have suffixed
we cannot have suffixed
you cannot have suffixed
they cannot have suffixed	I cannot have been suffixing
you cannot have been suffixing
she cannot have been suffixing
we cannot have been suffixing
you cannot have been suffixing
they cannot have been suffixing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I suffix?
can you suffix?
can she suffix?
can we suffix?
can you suffix?
can they suffix? 	can I be suffixing?
can you be suffixing?
can she be suffixing?
can we be suffixing?
can you be suffixing?
can they be suffixing? 	can I have suffixed?
can you have suffixed?
can she have suffixed?
can we have suffixed?
can you have suffixed?
can they have suffixed? 	can I have been suffixing?
can you have been suffixing?
can she have been suffixing?
can we have been suffixing?
can you have been suffixing?
can they have been suffixing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not suffix?
can you not suffix?
can she not suffix?
can we not suffix?
can you not suffix?
can they not suffix? 	can I not be suffixing?
can you not be suffixing?
can she not be suffixing?
can we not be suffixing?
can you not be suffixing?
can they not be suffixing? 	can I not have suffixed?
can you not have suffixed?
can she not have suffixed?
can we not have suffixed?
can you not have suffixed?
can they not have suffixed? 	can I not have been suffixing?
can you not have been suffixing?
can she not have been suffixing?
can we not have been suffixing?
can you not have been suffixing?
can they not have been suffixing?