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