I could louden you could louden he could louden we could louden you could louden they could louden
V-ing form
I could be loudening you could be loudening he could be loudening we could be loudening you could be loudening they could be loudening
Perfect
I could have loudened you could have loudened he could have loudened we could have loudened you could have loudened they could have loudened
V-ing perfect
I could have been loudening you could have been loudening he could have been loudening we could have been loudening you could have been loudening they could have been loudening
Negation
Simple form
I could not louden you could not louden he could not louden we could not louden you could not louden they could not louden
V-ing form
I could not be loudening you could not be loudening he could not be loudening we could not be loudening you could not be loudening they could not be loudening
Perfect
I could not have loudened you could not have loudened he could not have loudened we could not have loudened you could not have loudened they could not have loudened
V-ing perfect
I could not have been loudening you could not have been loudening he could not have been loudening we could not have been loudening you could not have been loudening they could not have been loudening
Interrogative form
Simple form
could I louden? could you louden? could he louden? could we louden? could you louden? could they louden?
V-ing form
could I be loudening? could you be loudening? could he be loudening? could we be loudening? could you be loudening? could they be loudening?
Perfect
could I have loudened? could you have loudened? could he have loudened? could we have loudened? could you have loudened? could they have loudened?
V-ing perfect
could I have been loudening? could you have been loudening? could he have been loudening? could we have been loudening? could you have been loudening? could they have been loudening?
Interro-negative form
Simple form
could I not louden? could you not louden? could he not louden? could we not louden? could you not louden? could they not louden?
V-ing form
could I not be loudening? could you not be loudening? could he not be loudening? could we not be loudening? could you not be loudening? could they not be loudening?
Perfect
could I not have loudened? could you not have loudened? could he not have loudened? could we not have loudened? could you not have loudened? could they not have loudened?
V-ing perfect
could I not have been loudening? could you not have been loudening? could he not have been loudening? could we not have been loudening? could you not have been loudening? could they not have been loudening?