English verb conjugation
COULD DECOLOURISE

Regular verb: decolourise - decolourised - decolourised

Affirmation

Simple form	V-ing form
I could decolourise you could decolourise he could decolourise we could decolourise you could decolourise they could decolourise	I could be decolourising you could be decolourising he could be decolourising we could be decolourising you could be decolourising they could be decolourising
Perfect	V-ing perfect
I could have decolourised you could have decolourised he could have decolourised we could have decolourised you could have decolourised they could have decolourised	I could have been decolourising you could have been decolourising he could have been decolourising we could have been decolourising you could have been decolourising they could have been decolourising

Negation

Simple form	V-ing form
I couldn't decolourise you couldn't decolourise he couldn't decolourise we couldn't decolourise you couldn't decolourise they couldn't decolourise	I couldn't be decolourising you couldn't be decolourising he couldn't be decolourising we couldn't be decolourising you couldn't be decolourising they couldn't be decolourising
Perfect	V-ing perfect
I couldn't have decolourised you couldn't have decolourised he couldn't have decolourised we couldn't have decolourised you couldn't have decolourised they couldn't have decolourised	I couldn't have been decolourising you couldn't have been decolourising he couldn't have been decolourising we couldn't have been decolourising you couldn't have been decolourising they couldn't have been decolourising

Interrogative form

Simple form	V-ing form
could I decolourise? could you decolourise? could he decolourise? could we decolourise? could you decolourise? could they decolourise?	could I be decolourising? could you be decolourising? could he be decolourising? could we be decolourising? could you be decolourising? could they be decolourising?
Perfect	V-ing perfect
could I have decolourised? could you have decolourised? could he have decolourised? could we have decolourised? could you have decolourised? could they have decolourised?	could I have been decolourising? could you have been decolourising? could he have been decolourising? could we have been decolourising? could you have been decolourising? could they have been decolourising?

Interro-negative form

Simple form	V-ing form
couldn't I decolourise? couldn't you decolourise? couldn't he decolourise? couldn't we decolourise? couldn't you decolourise? couldn't they decolourise?	couldn't I be decolourising? couldn't you be decolourising? couldn't he be decolourising? couldn't we be decolourising? couldn't you be decolourising? couldn't they be decolourising?
Perfect	V-ing perfect
couldn't I have decolourised? couldn't you have decolourised? couldn't he have decolourised? couldn't we have decolourised? couldn't you have decolourised? couldn't they have decolourised?	couldn't I have been decolourising? couldn't you have been decolourising? couldn't he have been decolourising? couldn't we have been decolourising? couldn't you have been decolourising? couldn't they have been decolourising?