could phosphoresce
Regular verb: phosphoresce - phosphoresced- phosphoresced

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could phosphoresce
you could phosphoresce
he could phosphoresce
we could phosphoresce
you could phosphoresce
they could phosphoresce 	I could be phosphorescing
you could be phosphorescing
he could be phosphorescing
we could be phosphorescing
you could be phosphorescing
they could be phosphorescing	I could have phosphoresced
you could have phosphoresced
he could have phosphoresced
we could have phosphoresced
you could have phosphoresced
they could have phosphoresced	I could have been phosphorescing
you could have been phosphorescing
he could have been phosphorescing
we could have been phosphorescing
you could have been phosphorescing
they could have been phosphorescing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't phosphoresce
you couldn't phosphoresce
he couldn't phosphoresce
we couldn't phosphoresce
you couldn't phosphoresce
they couldn't phosphoresce 	I couldn't be phosphorescing
you couldn't be phosphorescing
he couldn't be phosphorescing
we couldn't be phosphorescing
you couldn't be phosphorescing
they couldn't be phosphorescing	I couldn't have phosphoresced
you couldn't have phosphoresced
he couldn't have phosphoresced
we couldn't have phosphoresced
you couldn't have phosphoresced
they couldn't have phosphoresced	I couldn't have been phosphorescing
you couldn't have been phosphorescing
he couldn't have been phosphorescing
we couldn't have been phosphorescing
you couldn't have been phosphorescing
they couldn't have been phosphorescing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I phosphoresce?
could you phosphoresce?
could he phosphoresce?
could we phosphoresce?
could you phosphoresce?
could they phosphoresce? 	could I be phosphorescing?
could you be phosphorescing?
could he be phosphorescing?
could we be phosphorescing?
could you be phosphorescing?
could they be phosphorescing? 	could I have phosphoresced?
could you have phosphoresced?
could he have phosphoresced?
could we have phosphoresced?
could you have phosphoresced?
could they have phosphoresced? 	could I have been phosphorescing?
could you have been phosphorescing?
could he have been phosphorescing?
could we have been phosphorescing?
could you have been phosphorescing?
could they have been phosphorescing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I phosphoresce?
couldn't you phosphoresce?
couldn't he phosphoresce?
couldn't we phosphoresce?
couldn't you phosphoresce?
couldn't they phosphoresce? 	couldn't I be phosphorescing?
couldn't you be phosphorescing?
couldn't he be phosphorescing?
couldn't we be phosphorescing?
couldn't you be phosphorescing?
couldn't they be phosphorescing? 	couldn't I have phosphoresced?
couldn't you have phosphoresced?
couldn't he have phosphoresced?
couldn't we have phosphoresced?
couldn't you have phosphoresced?
couldn't they have phosphoresced? 	couldn't I have been phosphorescing?
couldn't you have been phosphorescing?
couldn't he have been phosphorescing?
couldn't we have been phosphorescing?
couldn't you have been phosphorescing?
couldn't they have been phosphorescing?