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