English verb conjugation
COULD GNASH

Regular verb: gnash - gnashed - gnashed

Affirmation

Simple form	V-ing form
I could gnash you could gnash he could gnash we could gnash you could gnash they could gnash	I could be gnashing you could be gnashing he could be gnashing we could be gnashing you could be gnashing they could be gnashing
Perfect	V-ing perfect
I could have gnashed you could have gnashed he could have gnashed we could have gnashed you could have gnashed they could have gnashed	I could have been gnashing you could have been gnashing he could have been gnashing we could have been gnashing you could have been gnashing they could have been gnashing

Negation

Simple form	V-ing form
I could not gnash you could not gnash he could not gnash we could not gnash you could not gnash they could not gnash	I could not be gnashing you could not be gnashing he could not be gnashing we could not be gnashing you could not be gnashing they could not be gnashing
Perfect	V-ing perfect
I could not have gnashed you could not have gnashed he could not have gnashed we could not have gnashed you could not have gnashed they could not have gnashed	I could not have been gnashing you could not have been gnashing he could not have been gnashing we could not have been gnashing you could not have been gnashing they could not have been gnashing

Interrogative form

Simple form	V-ing form
could I gnash? could you gnash? could he gnash? could we gnash? could you gnash? could they gnash?	could I be gnashing? could you be gnashing? could he be gnashing? could we be gnashing? could you be gnashing? could they be gnashing?
Perfect	V-ing perfect
could I have gnashed? could you have gnashed? could he have gnashed? could we have gnashed? could you have gnashed? could they have gnashed?	could I have been gnashing? could you have been gnashing? could he have been gnashing? could we have been gnashing? could you have been gnashing? could they have been gnashing?

Interro-negative form

Simple form	V-ing form
could I not gnash? could you not gnash? could he not gnash? could we not gnash? could you not gnash? could they not gnash?	could I not be gnashing? could you not be gnashing? could he not be gnashing? could we not be gnashing? could you not be gnashing? could they not be gnashing?
Perfect	V-ing perfect
could I not have gnashed? could you not have gnashed? could he not have gnashed? could we not have gnashed? could you not have gnashed? could they not have gnashed?	could I not have been gnashing? could you not have been gnashing? could he not have been gnashing? could we not have been gnashing? could you not have been gnashing? could they not have been gnashing?