English verb conjugation
COULD STERILISE

Regular verb: sterilise - sterilised - sterilised

Affirmation

Simple form	V-ing form
I could sterilise you could sterilise he could sterilise we could sterilise you could sterilise they could sterilise	I could be sterilising you could be sterilising he could be sterilising we could be sterilising you could be sterilising they could be sterilising
Perfect	V-ing perfect
I could have sterilised you could have sterilised he could have sterilised we could have sterilised you could have sterilised they could have sterilised	I could have been sterilising you could have been sterilising he could have been sterilising we could have been sterilising you could have been sterilising they could have been sterilising

Negation

Simple form	V-ing form
I could not sterilise you could not sterilise he could not sterilise we could not sterilise you could not sterilise they could not sterilise	I could not be sterilising you could not be sterilising he could not be sterilising we could not be sterilising you could not be sterilising they could not be sterilising
Perfect	V-ing perfect
I could not have sterilised you could not have sterilised he could not have sterilised we could not have sterilised you could not have sterilised they could not have sterilised	I could not have been sterilising you could not have been sterilising he could not have been sterilising we could not have been sterilising you could not have been sterilising they could not have been sterilising

Interrogative form

Simple form	V-ing form
could I sterilise? could you sterilise? could he sterilise? could we sterilise? could you sterilise? could they sterilise?	could I be sterilising? could you be sterilising? could he be sterilising? could we be sterilising? could you be sterilising? could they be sterilising?
Perfect	V-ing perfect
could I have sterilised? could you have sterilised? could he have sterilised? could we have sterilised? could you have sterilised? could they have sterilised?	could I have been sterilising? could you have been sterilising? could he have been sterilising? could we have been sterilising? could you have been sterilising? could they have been sterilising?

Interro-negative form

Simple form	V-ing form
could I not sterilise? could you not sterilise? could he not sterilise? could we not sterilise? could you not sterilise? could they not sterilise?	could I not be sterilising? could you not be sterilising? could he not be sterilising? could we not be sterilising? could you not be sterilising? could they not be sterilising?
Perfect	V-ing perfect
could I not have sterilised? could you not have sterilised? could he not have sterilised? could we not have sterilised? could you not have sterilised? could they not have sterilised?	could I not have been sterilising? could you not have been sterilising? could he not have been sterilising? could we not have been sterilising? could you not have been sterilising? could they not have been sterilising?