I could infiltrate you could infiltrate she could infiltrate we could infiltrate you could infiltrate they could infiltrate
V-ing form
I could be infiltrating you could be infiltrating she could be infiltrating we could be infiltrating you could be infiltrating they could be infiltrating
Perfect
I could have infiltrated you could have infiltrated she could have infiltrated we could have infiltrated you could have infiltrated they could have infiltrated
V-ing perfect
I could have been infiltrating you could have been infiltrating she could have been infiltrating we could have been infiltrating you could have been infiltrating they could have been infiltrating
Negation
Simple form
I couldn't infiltrate you couldn't infiltrate she couldn't infiltrate we couldn't infiltrate you couldn't infiltrate they couldn't infiltrate
V-ing form
I couldn't be infiltrating you couldn't be infiltrating she couldn't be infiltrating we couldn't be infiltrating you couldn't be infiltrating they couldn't be infiltrating
Perfect
I couldn't have infiltrated you couldn't have infiltrated she couldn't have infiltrated we couldn't have infiltrated you couldn't have infiltrated they couldn't have infiltrated
V-ing perfect
I couldn't have been infiltrating you couldn't have been infiltrating she couldn't have been infiltrating we couldn't have been infiltrating you couldn't have been infiltrating they couldn't have been infiltrating
Interrogative form
Simple form
could I infiltrate? could you infiltrate? could she infiltrate? could we infiltrate? could you infiltrate? could they infiltrate?
V-ing form
could I be infiltrating? could you be infiltrating? could she be infiltrating? could we be infiltrating? could you be infiltrating? could they be infiltrating?
Perfect
could I have infiltrated? could you have infiltrated? could she have infiltrated? could we have infiltrated? could you have infiltrated? could they have infiltrated?
V-ing perfect
could I have been infiltrating? could you have been infiltrating? could she have been infiltrating? could we have been infiltrating? could you have been infiltrating? could they have been infiltrating?
Interro-negative form
Simple form
couldn't I infiltrate? couldn't you infiltrate? couldn't she infiltrate? couldn't we infiltrate? couldn't you infiltrate? couldn't they infiltrate?
V-ing form
couldn't I be infiltrating? couldn't you be infiltrating? couldn't she be infiltrating? couldn't we be infiltrating? couldn't you be infiltrating? couldn't they be infiltrating?
Perfect
couldn't I have infiltrated? couldn't you have infiltrated? couldn't she have infiltrated? couldn't we have infiltrated? couldn't you have infiltrated? couldn't they have infiltrated?
V-ing perfect
couldn't I have been infiltrating? couldn't you have been infiltrating? couldn't she have been infiltrating? couldn't we have been infiltrating? couldn't you have been infiltrating? couldn't they have been infiltrating?