I could radiotelephone you could radiotelephone he could radiotelephone we could radiotelephone you could radiotelephone they could radiotelephone
V-ing form
I could be radiotelephoning you could be radiotelephoning he could be radiotelephoning we could be radiotelephoning you could be radiotelephoning they could be radiotelephoning
Perfect
I could have radiotelephoned you could have radiotelephoned he could have radiotelephoned we could have radiotelephoned you could have radiotelephoned they could have radiotelephoned
V-ing perfect
I could have been radiotelephoning you could have been radiotelephoning he could have been radiotelephoning we could have been radiotelephoning you could have been radiotelephoning they could have been radiotelephoning
Negation
Simple form
I could not radiotelephone you could not radiotelephone he could not radiotelephone we could not radiotelephone you could not radiotelephone they could not radiotelephone
V-ing form
I could not be radiotelephoning you could not be radiotelephoning he could not be radiotelephoning we could not be radiotelephoning you could not be radiotelephoning they could not be radiotelephoning
Perfect
I could not have radiotelephoned you could not have radiotelephoned he could not have radiotelephoned we could not have radiotelephoned you could not have radiotelephoned they could not have radiotelephoned
V-ing perfect
I could not have been radiotelephoning you could not have been radiotelephoning he could not have been radiotelephoning we could not have been radiotelephoning you could not have been radiotelephoning they could not have been radiotelephoning
Interrogative form
Simple form
could I radiotelephone? could you radiotelephone? could he radiotelephone? could we radiotelephone? could you radiotelephone? could they radiotelephone?
V-ing form
could I be radiotelephoning? could you be radiotelephoning? could he be radiotelephoning? could we be radiotelephoning? could you be radiotelephoning? could they be radiotelephoning?
Perfect
could I have radiotelephoned? could you have radiotelephoned? could he have radiotelephoned? could we have radiotelephoned? could you have radiotelephoned? could they have radiotelephoned?
V-ing perfect
could I have been radiotelephoning? could you have been radiotelephoning? could he have been radiotelephoning? could we have been radiotelephoning? could you have been radiotelephoning? could they have been radiotelephoning?
Interro-negative form
Simple form
could I not radiotelephone? could you not radiotelephone? could he not radiotelephone? could we not radiotelephone? could you not radiotelephone? could they not radiotelephone?
V-ing form
could I not be radiotelephoning? could you not be radiotelephoning? could he not be radiotelephoning? could we not be radiotelephoning? could you not be radiotelephoning? could they not be radiotelephoning?
Perfect
could I not have radiotelephoned? could you not have radiotelephoned? could he not have radiotelephoned? could we not have radiotelephoned? could you not have radiotelephoned? could they not have radiotelephoned?
V-ing perfect
could I not have been radiotelephoning? could you not have been radiotelephoning? could he not have been radiotelephoning? could we not have been radiotelephoning? could you not have been radiotelephoning? could they not have been radiotelephoning?