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