I could diffract you could diffract he could diffract we could diffract you could diffract they could diffract
V-ing form
I could be diffracting you could be diffracting he could be diffracting we could be diffracting you could be diffracting they could be diffracting
Perfect
I could have diffracted you could have diffracted he could have diffracted we could have diffracted you could have diffracted they could have diffracted
V-ing perfect
I could have been diffracting you could have been diffracting he could have been diffracting we could have been diffracting you could have been diffracting they could have been diffracting
Negation
Simple form
I could not diffract you could not diffract he could not diffract we could not diffract you could not diffract they could not diffract
V-ing form
I could not be diffracting you could not be diffracting he could not be diffracting we could not be diffracting you could not be diffracting they could not be diffracting
Perfect
I could not have diffracted you could not have diffracted he could not have diffracted we could not have diffracted you could not have diffracted they could not have diffracted
V-ing perfect
I could not have been diffracting you could not have been diffracting he could not have been diffracting we could not have been diffracting you could not have been diffracting they could not have been diffracting
Interrogative form
Simple form
could I diffract? could you diffract? could he diffract? could we diffract? could you diffract? could they diffract?
V-ing form
could I be diffracting? could you be diffracting? could he be diffracting? could we be diffracting? could you be diffracting? could they be diffracting?
Perfect
could I have diffracted? could you have diffracted? could he have diffracted? could we have diffracted? could you have diffracted? could they have diffracted?
V-ing perfect
could I have been diffracting? could you have been diffracting? could he have been diffracting? could we have been diffracting? could you have been diffracting? could they have been diffracting?
Interro-negative form
Simple form
could I not diffract? could you not diffract? could he not diffract? could we not diffract? could you not diffract? could they not diffract?
V-ing form
could I not be diffracting? could you not be diffracting? could he not be diffracting? could we not be diffracting? could you not be diffracting? could they not be diffracting?
Perfect
could I not have diffracted? could you not have diffracted? could he not have diffracted? could we not have diffracted? could you not have diffracted? could they not have diffracted?
V-ing perfect
could I not have been diffracting? could you not have been diffracting? could he not have been diffracting? could we not have been diffracting? could you not have been diffracting? could they not have been diffracting?