English verb conjugation
COULD SYNTHESISE

Regular verb: synthesise - synthesised - synthesised

Affirmation

Simple form	V-ing form
I could synthesise you could synthesise he could synthesise we could synthesise you could synthesise they could synthesise	I could be synthesising you could be synthesising he could be synthesising we could be synthesising you could be synthesising they could be synthesising
Perfect	V-ing perfect
I could have synthesised you could have synthesised he could have synthesised we could have synthesised you could have synthesised they could have synthesised	I could have been synthesising you could have been synthesising he could have been synthesising we could have been synthesising you could have been synthesising they could have been synthesising

Negation

Simple form	V-ing form
I couldn't synthesise you couldn't synthesise he couldn't synthesise we couldn't synthesise you couldn't synthesise they couldn't synthesise	I couldn't be synthesising you couldn't be synthesising he couldn't be synthesising we couldn't be synthesising you couldn't be synthesising they couldn't be synthesising
Perfect	V-ing perfect
I couldn't have synthesised you couldn't have synthesised he couldn't have synthesised we couldn't have synthesised you couldn't have synthesised they couldn't have synthesised	I couldn't have been synthesising you couldn't have been synthesising he couldn't have been synthesising we couldn't have been synthesising you couldn't have been synthesising they couldn't have been synthesising

Interrogative form

Simple form	V-ing form
could I synthesise? could you synthesise? could he synthesise? could we synthesise? could you synthesise? could they synthesise?	could I be synthesising? could you be synthesising? could he be synthesising? could we be synthesising? could you be synthesising? could they be synthesising?
Perfect	V-ing perfect
could I have synthesised? could you have synthesised? could he have synthesised? could we have synthesised? could you have synthesised? could they have synthesised?	could I have been synthesising? could you have been synthesising? could he have been synthesising? could we have been synthesising? could you have been synthesising? could they have been synthesising?

Interro-negative form

Simple form	V-ing form
couldn't I synthesise? couldn't you synthesise? couldn't he synthesise? couldn't we synthesise? couldn't you synthesise? couldn't they synthesise?	couldn't I be synthesising? couldn't you be synthesising? couldn't he be synthesising? couldn't we be synthesising? couldn't you be synthesising? couldn't they be synthesising?
Perfect	V-ing perfect
couldn't I have synthesised? couldn't you have synthesised? couldn't he have synthesised? couldn't we have synthesised? couldn't you have synthesised? couldn't they have synthesised?	couldn't I have been synthesising? couldn't you have been synthesising? couldn't he have been synthesising? couldn't we have been synthesising? couldn't you have been synthesising? couldn't they have been synthesising?