I could smash you could smash he could smash we could smash you could smash they could smash
V-ing form
I could be smashing you could be smashing he could be smashing we could be smashing you could be smashing they could be smashing
Perfect
I could have smashed you could have smashed he could have smashed we could have smashed you could have smashed they could have smashed
V-ing perfect
I could have been smashing you could have been smashing he could have been smashing we could have been smashing you could have been smashing they could have been smashing
Negation
Simple form
I couldn't smash you couldn't smash he couldn't smash we couldn't smash you couldn't smash they couldn't smash
V-ing form
I couldn't be smashing you couldn't be smashing he couldn't be smashing we couldn't be smashing you couldn't be smashing they couldn't be smashing
Perfect
I couldn't have smashed you couldn't have smashed he couldn't have smashed we couldn't have smashed you couldn't have smashed they couldn't have smashed
V-ing perfect
I couldn't have been smashing you couldn't have been smashing he couldn't have been smashing we couldn't have been smashing you couldn't have been smashing they couldn't have been smashing
Interrogative form
Simple form
could I smash? could you smash? could he smash? could we smash? could you smash? could they smash?
V-ing form
could I be smashing? could you be smashing? could he be smashing? could we be smashing? could you be smashing? could they be smashing?
Perfect
could I have smashed? could you have smashed? could he have smashed? could we have smashed? could you have smashed? could they have smashed?
V-ing perfect
could I have been smashing? could you have been smashing? could he have been smashing? could we have been smashing? could you have been smashing? could they have been smashing?
Interro-negative form
Simple form
couldn't I smash? couldn't you smash? couldn't he smash? couldn't we smash? couldn't you smash? couldn't they smash?
V-ing form
couldn't I be smashing? couldn't you be smashing? couldn't he be smashing? couldn't we be smashing? couldn't you be smashing? couldn't they be smashing?
Perfect
couldn't I have smashed? couldn't you have smashed? couldn't he have smashed? couldn't we have smashed? couldn't you have smashed? couldn't they have smashed?
V-ing perfect
couldn't I have been smashing? couldn't you have been smashing? couldn't he have been smashing? couldn't we have been smashing? couldn't you have been smashing? couldn't they have been smashing?