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 couldn't radiotelephone you couldn't radiotelephone he couldn't radiotelephone we couldn't radiotelephone you couldn't radiotelephone they couldn't radiotelephone
V-ing form
I couldn't be radiotelephoning you couldn't be radiotelephoning he couldn't be radiotelephoning we couldn't be radiotelephoning you couldn't be radiotelephoning they couldn't be radiotelephoning
Perfect
I couldn't have radiotelephoned you couldn't have radiotelephoned he couldn't have radiotelephoned we couldn't have radiotelephoned you couldn't have radiotelephoned they couldn't have radiotelephoned
V-ing perfect
I couldn't have been radiotelephoning you couldn't have been radiotelephoning he couldn't have been radiotelephoning we couldn't have been radiotelephoning you couldn't have been radiotelephoning they couldn't 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
couldn't I radiotelephone? couldn't you radiotelephone? couldn't he radiotelephone? couldn't we radiotelephone? couldn't you radiotelephone? couldn't they radiotelephone?
V-ing form
couldn't I be radiotelephoning? couldn't you be radiotelephoning? couldn't he be radiotelephoning? couldn't we be radiotelephoning? couldn't you be radiotelephoning? couldn't they be radiotelephoning?
Perfect
couldn't I have radiotelephoned? couldn't you have radiotelephoned? couldn't he have radiotelephoned? couldn't we have radiotelephoned? couldn't you have radiotelephoned? couldn't they have radiotelephoned?
V-ing perfect
couldn't I have been radiotelephoning? couldn't you have been radiotelephoning? couldn't he have been radiotelephoning? couldn't we have been radiotelephoning? couldn't you have been radiotelephoning? couldn't they have been radiotelephoning?