
Regular verb: inject - injected - injected
Simple form | V-ing form | 
| I could inject you could inject she could inject we could inject you could inject they could inject  | 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 | V-ing 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  | 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  | 
Simple form | V-ing form | 
| I couldn't inject you couldn't inject she 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 she couldn't be injecting we couldn't be injecting you couldn't be injecting they couldn't be injecting  | 
Perfect | V-ing perfect | 
| I couldn't have injected you couldn't have injected she 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 she couldn't have been injecting we couldn't have been injecting you couldn't have been injecting they couldn't have been injecting  | 
Simple form | V-ing form | 
| could I inject? could you inject? could she inject? could we inject? could you inject? could they inject?  | 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 | V-ing 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?  | 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?  | 
Simple form | V-ing form | 
| couldn't I inject? couldn't you inject? couldn't she 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 she be injecting? couldn't we be injecting? couldn't you be injecting? couldn't they be injecting?  | 
Perfect | V-ing perfect | 
| couldn't I have injected? couldn't you have injected? couldn't she 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 she have been injecting? couldn't we have been injecting? couldn't you have been injecting? couldn't they have been injecting?  |