I could handwash you could handwash he could handwash we could handwash you could handwash they could handwash
V-ing form
I could be handwashing you could be handwashing he could be handwashing we could be handwashing you could be handwashing they could be handwashing
Perfect
I could have handwashed you could have handwashed he could have handwashed we could have handwashed you could have handwashed they could have handwashed
V-ing perfect
I could have been handwashing you could have been handwashing he could have been handwashing we could have been handwashing you could have been handwashing they could have been handwashing
Negation
Simple form
I could not handwash you could not handwash he could not handwash we could not handwash you could not handwash they could not handwash
V-ing form
I could not be handwashing you could not be handwashing he could not be handwashing we could not be handwashing you could not be handwashing they could not be handwashing
Perfect
I could not have handwashed you could not have handwashed he could not have handwashed we could not have handwashed you could not have handwashed they could not have handwashed
V-ing perfect
I could not have been handwashing you could not have been handwashing he could not have been handwashing we could not have been handwashing you could not have been handwashing they could not have been handwashing
Interrogative form
Simple form
could I handwash? could you handwash? could he handwash? could we handwash? could you handwash? could they handwash?
V-ing form
could I be handwashing? could you be handwashing? could he be handwashing? could we be handwashing? could you be handwashing? could they be handwashing?
Perfect
could I have handwashed? could you have handwashed? could he have handwashed? could we have handwashed? could you have handwashed? could they have handwashed?
V-ing perfect
could I have been handwashing? could you have been handwashing? could he have been handwashing? could we have been handwashing? could you have been handwashing? could they have been handwashing?
Interro-negative form
Simple form
could I not handwash? could you not handwash? could he not handwash? could we not handwash? could you not handwash? could they not handwash?
V-ing form
could I not be handwashing? could you not be handwashing? could he not be handwashing? could we not be handwashing? could you not be handwashing? could they not be handwashing?
Perfect
could I not have handwashed? could you not have handwashed? could he not have handwashed? could we not have handwashed? could you not have handwashed? could they not have handwashed?
V-ing perfect
could I not have been handwashing? could you not have been handwashing? could he not have been handwashing? could we not have been handwashing? could you not have been handwashing? could they not have been handwashing?