I could refund you could refund he could refund we could refund you could refund they could refund
V-ing form
I could be refunding you could be refunding he could be refunding we could be refunding you could be refunding they could be refunding
Perfect
I could have refunded you could have refunded he could have refunded we could have refunded you could have refunded they could have refunded
V-ing perfect
I could have been refunding you could have been refunding he could have been refunding we could have been refunding you could have been refunding they could have been refunding
Negation
Simple form
I couldn't refund you couldn't refund he couldn't refund we couldn't refund you couldn't refund they couldn't refund
V-ing form
I couldn't be refunding you couldn't be refunding he couldn't be refunding we couldn't be refunding you couldn't be refunding they couldn't be refunding
Perfect
I couldn't have refunded you couldn't have refunded he couldn't have refunded we couldn't have refunded you couldn't have refunded they couldn't have refunded
V-ing perfect
I couldn't have been refunding you couldn't have been refunding he couldn't have been refunding we couldn't have been refunding you couldn't have been refunding they couldn't have been refunding
Interrogative form
Simple form
could I refund? could you refund? could he refund? could we refund? could you refund? could they refund?
V-ing form
could I be refunding? could you be refunding? could he be refunding? could we be refunding? could you be refunding? could they be refunding?
Perfect
could I have refunded? could you have refunded? could he have refunded? could we have refunded? could you have refunded? could they have refunded?
V-ing perfect
could I have been refunding? could you have been refunding? could he have been refunding? could we have been refunding? could you have been refunding? could they have been refunding?
Interro-negative form
Simple form
couldn't I refund? couldn't you refund? couldn't he refund? couldn't we refund? couldn't you refund? couldn't they refund?
V-ing form
couldn't I be refunding? couldn't you be refunding? couldn't he be refunding? couldn't we be refunding? couldn't you be refunding? couldn't they be refunding?
Perfect
couldn't I have refunded? couldn't you have refunded? couldn't he have refunded? couldn't we have refunded? couldn't you have refunded? couldn't they have refunded?
V-ing perfect
couldn't I have been refunding? couldn't you have been refunding? couldn't he have been refunding? couldn't we have been refunding? couldn't you have been refunding? couldn't they have been refunding?