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