English verb conjugation
COULD DECODE

Regular verb: decode - decoded - decoded

Affirmation

Simple form	V-ing form
I could decode you could decode he could decode we could decode you could decode they could decode	I could be decoding you could be decoding he could be decoding we could be decoding you could be decoding they could be decoding
Perfect	V-ing perfect
I could have decoded you could have decoded he could have decoded we could have decoded you could have decoded they could have decoded	I could have been decoding you could have been decoding he could have been decoding we could have been decoding you could have been decoding they could have been decoding

Negation

Simple form	V-ing form
I couldn't decode you couldn't decode he couldn't decode we couldn't decode you couldn't decode they couldn't decode	I couldn't be decoding you couldn't be decoding he couldn't be decoding we couldn't be decoding you couldn't be decoding they couldn't be decoding
Perfect	V-ing perfect
I couldn't have decoded you couldn't have decoded he couldn't have decoded we couldn't have decoded you couldn't have decoded they couldn't have decoded	I couldn't have been decoding you couldn't have been decoding he couldn't have been decoding we couldn't have been decoding you couldn't have been decoding they couldn't have been decoding

Interrogative form

Simple form	V-ing form
could I decode? could you decode? could he decode? could we decode? could you decode? could they decode?	could I be decoding? could you be decoding? could he be decoding? could we be decoding? could you be decoding? could they be decoding?
Perfect	V-ing perfect
could I have decoded? could you have decoded? could he have decoded? could we have decoded? could you have decoded? could they have decoded?	could I have been decoding? could you have been decoding? could he have been decoding? could we have been decoding? could you have been decoding? could they have been decoding?

Interro-negative form

Simple form	V-ing form
couldn't I decode? couldn't you decode? couldn't he decode? couldn't we decode? couldn't you decode? couldn't they decode?	couldn't I be decoding? couldn't you be decoding? couldn't he be decoding? couldn't we be decoding? couldn't you be decoding? couldn't they be decoding?
Perfect	V-ing perfect
couldn't I have decoded? couldn't you have decoded? couldn't he have decoded? couldn't we have decoded? couldn't you have decoded? couldn't they have decoded?	couldn't I have been decoding? couldn't you have been decoding? couldn't he have been decoding? couldn't we have been decoding? couldn't you have been decoding? couldn't they have been decoding?