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 couldn't gnash you couldn't gnash he couldn't gnash we couldn't gnash you couldn't gnash they couldn't gnash	I couldn't be gnashing you couldn't be gnashing he couldn't be gnashing we couldn't be gnashing you couldn't be gnashing they couldn't be gnashing
Perfect	V-ing perfect
I couldn't have gnashed you couldn't have gnashed he couldn't have gnashed we couldn't have gnashed you couldn't have gnashed they couldn't have gnashed	I couldn't have been gnashing you couldn't have been gnashing he couldn't have been gnashing we couldn't have been gnashing you couldn't have been gnashing they couldn't 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
couldn't I gnash? couldn't you gnash? couldn't he gnash? couldn't we gnash? couldn't you gnash? couldn't they gnash?	couldn't I be gnashing? couldn't you be gnashing? couldn't he be gnashing? couldn't we be gnashing? couldn't you be gnashing? couldn't they be gnashing?
Perfect	V-ing perfect
couldn't I have gnashed? couldn't you have gnashed? couldn't he have gnashed? couldn't we have gnashed? couldn't you have gnashed? couldn't they have gnashed?	couldn't I have been gnashing? couldn't you have been gnashing? couldn't he have been gnashing? couldn't we have been gnashing? couldn't you have been gnashing? couldn't they have been gnashing?