English verb conjugation
COULD PHOTOSYNTHESISE

Regular verb: photosynthesise - photosynthesised - photosynthesised

Affirmation

Simple form	V-ing form
I could photosynthesise you could photosynthesise he could photosynthesise we could photosynthesise you could photosynthesise they could photosynthesise	I could be photosynthesising you could be photosynthesising he could be photosynthesising we could be photosynthesising you could be photosynthesising they could be photosynthesising
Perfect	V-ing perfect
I could have photosynthesised you could have photosynthesised he could have photosynthesised we could have photosynthesised you could have photosynthesised they could have photosynthesised	I could have been photosynthesising you could have been photosynthesising he could have been photosynthesising we could have been photosynthesising you could have been photosynthesising they could have been photosynthesising

Negation

Simple form	V-ing form
I couldn't photosynthesise you couldn't photosynthesise he couldn't photosynthesise we couldn't photosynthesise you couldn't photosynthesise they couldn't photosynthesise	I couldn't be photosynthesising you couldn't be photosynthesising he couldn't be photosynthesising we couldn't be photosynthesising you couldn't be photosynthesising they couldn't be photosynthesising
Perfect	V-ing perfect
I couldn't have photosynthesised you couldn't have photosynthesised he couldn't have photosynthesised we couldn't have photosynthesised you couldn't have photosynthesised they couldn't have photosynthesised	I couldn't have been photosynthesising you couldn't have been photosynthesising he couldn't have been photosynthesising we couldn't have been photosynthesising you couldn't have been photosynthesising they couldn't have been photosynthesising

Interrogative form

Simple form	V-ing form
could I photosynthesise? could you photosynthesise? could he photosynthesise? could we photosynthesise? could you photosynthesise? could they photosynthesise?	could I be photosynthesising? could you be photosynthesising? could he be photosynthesising? could we be photosynthesising? could you be photosynthesising? could they be photosynthesising?
Perfect	V-ing perfect
could I have photosynthesised? could you have photosynthesised? could he have photosynthesised? could we have photosynthesised? could you have photosynthesised? could they have photosynthesised?	could I have been photosynthesising? could you have been photosynthesising? could he have been photosynthesising? could we have been photosynthesising? could you have been photosynthesising? could they have been photosynthesising?

Interro-negative form

Simple form	V-ing form
couldn't I photosynthesise? couldn't you photosynthesise? couldn't he photosynthesise? couldn't we photosynthesise? couldn't you photosynthesise? couldn't they photosynthesise?	couldn't I be photosynthesising? couldn't you be photosynthesising? couldn't he be photosynthesising? couldn't we be photosynthesising? couldn't you be photosynthesising? couldn't they be photosynthesising?
Perfect	V-ing perfect
couldn't I have photosynthesised? couldn't you have photosynthesised? couldn't he have photosynthesised? couldn't we have photosynthesised? couldn't you have photosynthesised? couldn't they have photosynthesised?	couldn't I have been photosynthesising? couldn't you have been photosynthesising? couldn't he have been photosynthesising? couldn't we have been photosynthesising? couldn't you have been photosynthesising? couldn't they have been photosynthesising?