English verb conjugation
COULD FAX

Regular verb: fax - faxed - faxed

Affirmation

Simple form	V-ing form
I could fax you could fax she could fax we could fax you could fax they could fax	I could be faxing you could be faxing she could be faxing we could be faxing you could be faxing they could be faxing
Perfect	V-ing perfect
I could have faxed you could have faxed she could have faxed we could have faxed you could have faxed they could have faxed	I could have been faxing you could have been faxing she could have been faxing we could have been faxing you could have been faxing they could have been faxing

Negation

Simple form	V-ing form
I couldn't fax you couldn't fax she couldn't fax we couldn't fax you couldn't fax they couldn't fax	I couldn't be faxing you couldn't be faxing she couldn't be faxing we couldn't be faxing you couldn't be faxing they couldn't be faxing
Perfect	V-ing perfect
I couldn't have faxed you couldn't have faxed she couldn't have faxed we couldn't have faxed you couldn't have faxed they couldn't have faxed	I couldn't have been faxing you couldn't have been faxing she couldn't have been faxing we couldn't have been faxing you couldn't have been faxing they couldn't have been faxing

Interrogative form

Simple form	V-ing form
could I fax? could you fax? could she fax? could we fax? could you fax? could they fax?	could I be faxing? could you be faxing? could she be faxing? could we be faxing? could you be faxing? could they be faxing?
Perfect	V-ing perfect
could I have faxed? could you have faxed? could she have faxed? could we have faxed? could you have faxed? could they have faxed?	could I have been faxing? could you have been faxing? could she have been faxing? could we have been faxing? could you have been faxing? could they have been faxing?

Interro-negative form

Simple form	V-ing form
couldn't I fax? couldn't you fax? couldn't she fax? couldn't we fax? couldn't you fax? couldn't they fax?	couldn't I be faxing? couldn't you be faxing? couldn't she be faxing? couldn't we be faxing? couldn't you be faxing? couldn't they be faxing?
Perfect	V-ing perfect
couldn't I have faxed? couldn't you have faxed? couldn't she have faxed? couldn't we have faxed? couldn't you have faxed? couldn't they have faxed?	couldn't I have been faxing? couldn't you have been faxing? couldn't she have been faxing? couldn't we have been faxing? couldn't you have been faxing? couldn't they have been faxing?