can water-ski
Regular verb: water-ski - water-skied- water-skied

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can water-ski
you can water-ski
he can water-ski
we can water-ski
you can water-ski
they can water-ski 	I can be water-skiing
you can be water-skiing
he can be water-skiing
we can be water-skiing
you can be water-skiing
they can be water-skiing	I can have water-skied
you can have water-skied
he can have water-skied
we can have water-skied
you can have water-skied
they can have water-skied	I can have been water-skiing
you can have been water-skiing
he can have been water-skiing
we can have been water-skiing
you can have been water-skiing
they can have been water-skiing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot water-ski
you cannot water-ski
he cannot water-ski
we cannot water-ski
you cannot water-ski
they cannot water-ski 	I cannot be water-skiing
you cannot be water-skiing
he cannot be water-skiing
we cannot be water-skiing
you cannot be water-skiing
they cannot be water-skiing	I cannot have water-skied
you cannot have water-skied
he cannot have water-skied
we cannot have water-skied
you cannot have water-skied
they cannot have water-skied	I cannot have been water-skiing
you cannot have been water-skiing
he cannot have been water-skiing
we cannot have been water-skiing
you cannot have been water-skiing
they cannot have been water-skiing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I water-ski?
can you water-ski?
can he water-ski?
can we water-ski?
can you water-ski?
can they water-ski? 	can I be water-skiing?
can you be water-skiing?
can he be water-skiing?
can we be water-skiing?
can you be water-skiing?
can they be water-skiing? 	can I have water-skied?
can you have water-skied?
can he have water-skied?
can we have water-skied?
can you have water-skied?
can they have water-skied? 	can I have been water-skiing?
can you have been water-skiing?
can he have been water-skiing?
can we have been water-skiing?
can you have been water-skiing?
can they have been water-skiing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not water-ski?
can you not water-ski?
can he not water-ski?
can we not water-ski?
can you not water-ski?
can they not water-ski? 	can I not be water-skiing?
can you not be water-skiing?
can he not be water-skiing?
can we not be water-skiing?
can you not be water-skiing?
can they not be water-skiing? 	can I not have water-skied?
can you not have water-skied?
can he not have water-skied?
can we not have water-skied?
can you not have water-skied?
can they not have water-skied? 	can I not have been water-skiing?
can you not have been water-skiing?
can he not have been water-skiing?
can we not have been water-skiing?
can you not have been water-skiing?
can they not have been water-skiing?