could dematerialise
Regular verb: dematerialise - dematerialised- dematerialised

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could dematerialise
you could dematerialise
he could dematerialise
we could dematerialise
you could dematerialise
they could dematerialise 	I could be dematerialising
you could be dematerialising
he could be dematerialising
we could be dematerialising
you could be dematerialising
they could be dematerialising	I could have dematerialised
you could have dematerialised
he could have dematerialised
we could have dematerialised
you could have dematerialised
they could have dematerialised	I could have been dematerialising
you could have been dematerialising
he could have been dematerialising
we could have been dematerialising
you could have been dematerialising
they could have been dematerialising	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not dematerialise
you could not dematerialise
he could not dematerialise
we could not dematerialise
you could not dematerialise
they could not dematerialise 	I could not be dematerialising
you could not be dematerialising
he could not be dematerialising
we could not be dematerialising
you could not be dematerialising
they could not be dematerialising	I could not have dematerialised
you could not have dematerialised
he could not have dematerialised
we could not have dematerialised
you could not have dematerialised
they could not have dematerialised	I could not have been dematerialising
you could not have been dematerialising
he could not have been dematerialising
we could not have been dematerialising
you could not have been dematerialising
they could not have been dematerialising	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I dematerialise?
could you dematerialise?
could he dematerialise?
could we dematerialise?
could you dematerialise?
could they dematerialise? 	could I be dematerialising?
could you be dematerialising?
could he be dematerialising?
could we be dematerialising?
could you be dematerialising?
could they be dematerialising? 	could I have dematerialised?
could you have dematerialised?
could he have dematerialised?
could we have dematerialised?
could you have dematerialised?
could they have dematerialised? 	could I have been dematerialising?
could you have been dematerialising?
could he have been dematerialising?
could we have been dematerialising?
could you have been dematerialising?
could they have been dematerialising? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not dematerialise?
could you not dematerialise?
could he not dematerialise?
could we not dematerialise?
could you not dematerialise?
could they not dematerialise? 	could I not be dematerialising?
could you not be dematerialising?
could he not be dematerialising?
could we not be dematerialising?
could you not be dematerialising?
could they not be dematerialising? 	could I not have dematerialised?
could you not have dematerialised?
could he not have dematerialised?
could we not have dematerialised?
could you not have dematerialised?
could they not have dematerialised? 	could I not have been dematerialising?
could you not have been dematerialising?
could he not have been dematerialising?
could we not have been dematerialising?
could you not have been dematerialising?
could they not have been dematerialising?