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