I could inject you could inject she could inject we could inject you could inject they could inject
V-ing form
I could be injecting you could be injecting she could be injecting we could be injecting you could be injecting they could be injecting
Perfect
I could have injected you could have injected she could have injected we could have injected you could have injected they could have injected
V-ing perfect
I could have been injecting you could have been injecting she could have been injecting we could have been injecting you could have been injecting they could have been injecting
Negation
Simple form
I could not inject you could not inject she could not inject we could not inject you could not inject they could not inject
V-ing form
I could not be injecting you could not be injecting she could not be injecting we could not be injecting you could not be injecting they could not be injecting
Perfect
I could not have injected you could not have injected she could not have injected we could not have injected you could not have injected they could not have injected
V-ing perfect
I could not have been injecting you could not have been injecting she could not have been injecting we could not have been injecting you could not have been injecting they could not have been injecting
Interrogative form
Simple form
could I inject? could you inject? could she inject? could we inject? could you inject? could they inject?
V-ing form
could I be injecting? could you be injecting? could she be injecting? could we be injecting? could you be injecting? could they be injecting?
Perfect
could I have injected? could you have injected? could she have injected? could we have injected? could you have injected? could they have injected?
V-ing perfect
could I have been injecting? could you have been injecting? could she have been injecting? could we have been injecting? could you have been injecting? could they have been injecting?
Interro-negative form
Simple form
could I not inject? could you not inject? could she not inject? could we not inject? could you not inject? could they not inject?
V-ing form
could I not be injecting? could you not be injecting? could she not be injecting? could we not be injecting? could you not be injecting? could they not be injecting?
Perfect
could I not have injected? could you not have injected? could she not have injected? could we not have injected? could you not have injected? could they not have injected?
V-ing perfect
could I not have been injecting? could you not have been injecting? could she not have been injecting? could we not have been injecting? could you not have been injecting? could they not have been injecting?