could inject
Regular verb: inject - injected- injected

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could inject
you could inject
he could inject
we could inject
you could inject
they could inject 	I could be injecting
you could be injecting
he could be injecting
we could be injecting
you could be injecting
they could be injecting	I could have injected
you could have injected
he could have injected
we could have injected
you could have injected
they could have injected	I could have been injecting
you could have been injecting
he could have been injecting
we could have been injecting
you could have been injecting
they could have been injecting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't inject
you couldn't inject
he couldn't inject
we couldn't inject
you couldn't inject
they couldn't inject 	I couldn't be injecting
you couldn't be injecting
he couldn't be injecting
we couldn't be injecting
you couldn't be injecting
they couldn't be injecting	I couldn't have injected
you couldn't have injected
he couldn't have injected
we couldn't have injected
you couldn't have injected
they couldn't have injected	I couldn't have been injecting
you couldn't have been injecting
he couldn't have been injecting
we couldn't have been injecting
you couldn't have been injecting
they couldn't have been injecting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I inject?
could you inject?
could he inject?
could we inject?
could you inject?
could they inject? 	could I be injecting?
could you be injecting?
could he be injecting?
could we be injecting?
could you be injecting?
could they be injecting? 	could I have injected?
could you have injected?
could he have injected?
could we have injected?
could you have injected?
could they have injected? 	could I have been injecting?
could you have been injecting?
could he have been injecting?
could we have been injecting?
could you have been injecting?
could they have been injecting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I inject?
couldn't you inject?
couldn't he inject?
couldn't we inject?
couldn't you inject?
couldn't they inject? 	couldn't I be injecting?
couldn't you be injecting?
couldn't he be injecting?
couldn't we be injecting?
couldn't you be injecting?
couldn't they be injecting? 	couldn't I have injected?
couldn't you have injected?
couldn't he have injected?
couldn't we have injected?
couldn't you have injected?
couldn't they have injected? 	couldn't I have been injecting?
couldn't you have been injecting?
couldn't he have been injecting?
couldn't we have been injecting?
couldn't you have been injecting?
couldn't they have been injecting?