can whistle
Regular verb: whistle - whistled- whistled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can whistle
you can whistle
she can whistle
we can whistle
you can whistle
they can whistle 	I can be whistling
you can be whistling
she can be whistling
we can be whistling
you can be whistling
they can be whistling	I can have whistled
you can have whistled
she can have whistled
we can have whistled
you can have whistled
they can have whistled	I can have been whistling
you can have been whistling
she can have been whistling
we can have been whistling
you can have been whistling
they can have been whistling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't whistle
you can't whistle
she can't whistle
we can't whistle
you can't whistle
they can't whistle 	I can't be whistling
you can't be whistling
she can't be whistling
we can't be whistling
you can't be whistling
they can't be whistling	I can't have whistled
you can't have whistled
she can't have whistled
we can't have whistled
you can't have whistled
they can't have whistled	I can't have been whistling
you can't have been whistling
she can't have been whistling
we can't have been whistling
you can't have been whistling
they can't have been whistling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I whistle?
can you whistle?
can she whistle?
can we whistle?
can you whistle?
can they whistle? 	can I be whistling?
can you be whistling?
can she be whistling?
can we be whistling?
can you be whistling?
can they be whistling? 	can I have whistled?
can you have whistled?
can she have whistled?
can we have whistled?
can you have whistled?
can they have whistled? 	can I have been whistling?
can you have been whistling?
can she have been whistling?
can we have been whistling?
can you have been whistling?
can they have been whistling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I whistle?
can't you whistle?
can't she whistle?
can't we whistle?
can't you whistle?
can't they whistle? 	can't I be whistling?
can't you be whistling?
can't she be whistling?
can't we be whistling?
can't you be whistling?
can't they be whistling? 	can't I have whistled?
can't you have whistled?
can't she have whistled?
can't we have whistled?
can't you have whistled?
can't they have whistled? 	can't I have been whistling?
can't you have been whistling?
can't she have been whistling?
can't we have been whistling?
can't you have been whistling?
can't they have been whistling?