English verb conjugation
COULD SERVICE

Regular verb: service - serviced - serviced

Affirmation

Simple form	V-ing form
I could service you could service he could service we could service you could service they could service	I could be servicing you could be servicing he could be servicing we could be servicing you could be servicing they could be servicing
Perfect	V-ing perfect
I could have serviced you could have serviced he could have serviced we could have serviced you could have serviced they could have serviced	I could have been servicing you could have been servicing he could have been servicing we could have been servicing you could have been servicing they could have been servicing

Negation

Simple form	V-ing form
I couldn't service you couldn't service he couldn't service we couldn't service you couldn't service they couldn't service	I couldn't be servicing you couldn't be servicing he couldn't be servicing we couldn't be servicing you couldn't be servicing they couldn't be servicing
Perfect	V-ing perfect
I couldn't have serviced you couldn't have serviced he couldn't have serviced we couldn't have serviced you couldn't have serviced they couldn't have serviced	I couldn't have been servicing you couldn't have been servicing he couldn't have been servicing we couldn't have been servicing you couldn't have been servicing they couldn't have been servicing

Interrogative form

Simple form	V-ing form
could I service? could you service? could he service? could we service? could you service? could they service?	could I be servicing? could you be servicing? could he be servicing? could we be servicing? could you be servicing? could they be servicing?
Perfect	V-ing perfect
could I have serviced? could you have serviced? could he have serviced? could we have serviced? could you have serviced? could they have serviced?	could I have been servicing? could you have been servicing? could he have been servicing? could we have been servicing? could you have been servicing? could they have been servicing?

Interro-negative form

Simple form	V-ing form
couldn't I service? couldn't you service? couldn't he service? couldn't we service? couldn't you service? couldn't they service?	couldn't I be servicing? couldn't you be servicing? couldn't he be servicing? couldn't we be servicing? couldn't you be servicing? couldn't they be servicing?
Perfect	V-ing perfect
couldn't I have serviced? couldn't you have serviced? couldn't he have serviced? couldn't we have serviced? couldn't you have serviced? couldn't they have serviced?	couldn't I have been servicing? couldn't you have been servicing? couldn't he have been servicing? couldn't we have been servicing? couldn't you have been servicing? couldn't they have been servicing?