I could decalcify you could decalcify he could decalcify we could decalcify you could decalcify they could decalcify
V-ing form
I could be decalcifying you could be decalcifying he could be decalcifying we could be decalcifying you could be decalcifying they could be decalcifying
Perfect
I could have decalcified you could have decalcified he could have decalcified we could have decalcified you could have decalcified they could have decalcified
V-ing perfect
I could have been decalcifying you could have been decalcifying he could have been decalcifying we could have been decalcifying you could have been decalcifying they could have been decalcifying
Negation
Simple form
I could not decalcify you could not decalcify he could not decalcify we could not decalcify you could not decalcify they could not decalcify
V-ing form
I could not be decalcifying you could not be decalcifying he could not be decalcifying we could not be decalcifying you could not be decalcifying they could not be decalcifying
Perfect
I could not have decalcified you could not have decalcified he could not have decalcified we could not have decalcified you could not have decalcified they could not have decalcified
V-ing perfect
I could not have been decalcifying you could not have been decalcifying he could not have been decalcifying we could not have been decalcifying you could not have been decalcifying they could not have been decalcifying
Interrogative form
Simple form
could I decalcify? could you decalcify? could he decalcify? could we decalcify? could you decalcify? could they decalcify?
V-ing form
could I be decalcifying? could you be decalcifying? could he be decalcifying? could we be decalcifying? could you be decalcifying? could they be decalcifying?
Perfect
could I have decalcified? could you have decalcified? could he have decalcified? could we have decalcified? could you have decalcified? could they have decalcified?
V-ing perfect
could I have been decalcifying? could you have been decalcifying? could he have been decalcifying? could we have been decalcifying? could you have been decalcifying? could they have been decalcifying?
Interro-negative form
Simple form
could I not decalcify? could you not decalcify? could he not decalcify? could we not decalcify? could you not decalcify? could they not decalcify?
V-ing form
could I not be decalcifying? could you not be decalcifying? could he not be decalcifying? could we not be decalcifying? could you not be decalcifying? could they not be decalcifying?
Perfect
could I not have decalcified? could you not have decalcified? could he not have decalcified? could we not have decalcified? could you not have decalcified? could they not have decalcified?
V-ing perfect
could I not have been decalcifying? could you not have been decalcifying? could he not have been decalcifying? could we not have been decalcifying? could you not have been decalcifying? could they not have been decalcifying?