I could encounter you could encounter he could encounter we could encounter you could encounter they could encounter
V-ing form
I could be encountering you could be encountering he could be encountering we could be encountering you could be encountering they could be encountering
Perfect
I could have encountered you could have encountered he could have encountered we could have encountered you could have encountered they could have encountered
V-ing perfect
I could have been encountering you could have been encountering he could have been encountering we could have been encountering you could have been encountering they could have been encountering
Negation
Simple form
I could not encounter you could not encounter he could not encounter we could not encounter you could not encounter they could not encounter
V-ing form
I could not be encountering you could not be encountering he could not be encountering we could not be encountering you could not be encountering they could not be encountering
Perfect
I could not have encountered you could not have encountered he could not have encountered we could not have encountered you could not have encountered they could not have encountered
V-ing perfect
I could not have been encountering you could not have been encountering he could not have been encountering we could not have been encountering you could not have been encountering they could not have been encountering
Interrogative form
Simple form
could I encounter? could you encounter? could he encounter? could we encounter? could you encounter? could they encounter?
V-ing form
could I be encountering? could you be encountering? could he be encountering? could we be encountering? could you be encountering? could they be encountering?
Perfect
could I have encountered? could you have encountered? could he have encountered? could we have encountered? could you have encountered? could they have encountered?
V-ing perfect
could I have been encountering? could you have been encountering? could he have been encountering? could we have been encountering? could you have been encountering? could they have been encountering?
Interro-negative form
Simple form
could I not encounter? could you not encounter? could he not encounter? could we not encounter? could you not encounter? could they not encounter?
V-ing form
could I not be encountering? could you not be encountering? could he not be encountering? could we not be encountering? could you not be encountering? could they not be encountering?
Perfect
could I not have encountered? could you not have encountered? could he not have encountered? could we not have encountered? could you not have encountered? could they not have encountered?
V-ing perfect
could I not have been encountering? could you not have been encountering? could he not have been encountering? could we not have been encountering? could you not have been encountering? could they not have been encountering?