can flag
Regular verb: flag - flagged- flagged

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can flag
you can flag
he can flag
we can flag
you can flag
they can flag 	I can be flagging
you can be flagging
he can be flagging
we can be flagging
you can be flagging
they can be flagging	I can have flagged
you can have flagged
he can have flagged
we can have flagged
you can have flagged
they can have flagged	I can have been flagging
you can have been flagging
he can have been flagging
we can have been flagging
you can have been flagging
they can have been flagging	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can't flag
you can't flag
he can't flag
we can't flag
you can't flag
they can't flag 	I can't be flagging
you can't be flagging
he can't be flagging
we can't be flagging
you can't be flagging
they can't be flagging	I can't have flagged
you can't have flagged
he can't have flagged
we can't have flagged
you can't have flagged
they can't have flagged	I can't have been flagging
you can't have been flagging
he can't have been flagging
we can't have been flagging
you can't have been flagging
they can't have been flagging	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I flag?
can you flag?
can he flag?
can we flag?
can you flag?
can they flag? 	can I be flagging?
can you be flagging?
can he be flagging?
can we be flagging?
can you be flagging?
can they be flagging? 	can I have flagged?
can you have flagged?
can he have flagged?
can we have flagged?
can you have flagged?
can they have flagged? 	can I have been flagging?
can you have been flagging?
can he have been flagging?
can we have been flagging?
can you have been flagging?
can they have been flagging? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can't I flag?
can't you flag?
can't he flag?
can't we flag?
can't you flag?
can't they flag? 	can't I be flagging?
can't you be flagging?
can't he be flagging?
can't we be flagging?
can't you be flagging?
can't they be flagging? 	can't I have flagged?
can't you have flagged?
can't he have flagged?
can't we have flagged?
can't you have flagged?
can't they have flagged? 	can't I have been flagging?
can't you have been flagging?
can't he have been flagging?
can't we have been flagging?
can't you have been flagging?
can't they have been flagging?