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