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