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