can titter
Regular verb: titter - tittered- tittered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can titter
you can titter
he can titter
we can titter
you can titter
they can titter 	I can be tittering
you can be tittering
he can be tittering
we can be tittering
you can be tittering
they can be tittering	I can have tittered
you can have tittered
he can have tittered
we can have tittered
you can have tittered
they can have tittered	I can have been tittering
you can have been tittering
he can have been tittering
we can have been tittering
you can have been tittering
they can have been tittering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't titter
you can't titter
he can't titter
we can't titter
you can't titter
they can't titter 	I can't be tittering
you can't be tittering
he can't be tittering
we can't be tittering
you can't be tittering
they can't be tittering	I can't have tittered
you can't have tittered
he can't have tittered
we can't have tittered
you can't have tittered
they can't have tittered	I can't have been tittering
you can't have been tittering
he can't have been tittering
we can't have been tittering
you can't have been tittering
they can't have been tittering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I titter?
can you titter?
can he titter?
can we titter?
can you titter?
can they titter? 	can I be tittering?
can you be tittering?
can he be tittering?
can we be tittering?
can you be tittering?
can they be tittering? 	can I have tittered?
can you have tittered?
can he have tittered?
can we have tittered?
can you have tittered?
can they have tittered? 	can I have been tittering?
can you have been tittering?
can he have been tittering?
can we have been tittering?
can you have been tittering?
can they have been tittering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I titter?
can't you titter?
can't he titter?
can't we titter?
can't you titter?
can't they titter? 	can't I be tittering?
can't you be tittering?
can't he be tittering?
can't we be tittering?
can't you be tittering?
can't they be tittering? 	can't I have tittered?
can't you have tittered?
can't he have tittered?
can't we have tittered?
can't you have tittered?
can't they have tittered? 	can't I have been tittering?
can't you have been tittering?
can't he have been tittering?
can't we have been tittering?
can't you have been tittering?
can't they have been tittering?