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