could sprout
Regular verb: sprout - sprouted- sprouted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could sprout
you could sprout
she could sprout
we could sprout
you could sprout
they could sprout 	I could be sprouting
you could be sprouting
she could be sprouting
we could be sprouting
you could be sprouting
they could be sprouting	I could have sprouted
you could have sprouted
she could have sprouted
we could have sprouted
you could have sprouted
they could have sprouted	I could have been sprouting
you could have been sprouting
she could have been sprouting
we could have been sprouting
you could have been sprouting
they could have been sprouting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't sprout
you couldn't sprout
she couldn't sprout
we couldn't sprout
you couldn't sprout
they couldn't sprout 	I couldn't be sprouting
you couldn't be sprouting
she couldn't be sprouting
we couldn't be sprouting
you couldn't be sprouting
they couldn't be sprouting	I couldn't have sprouted
you couldn't have sprouted
she couldn't have sprouted
we couldn't have sprouted
you couldn't have sprouted
they couldn't have sprouted	I couldn't have been sprouting
you couldn't have been sprouting
she couldn't have been sprouting
we couldn't have been sprouting
you couldn't have been sprouting
they couldn't have been sprouting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I sprout?
could you sprout?
could she sprout?
could we sprout?
could you sprout?
could they sprout? 	could I be sprouting?
could you be sprouting?
could she be sprouting?
could we be sprouting?
could you be sprouting?
could they be sprouting? 	could I have sprouted?
could you have sprouted?
could she have sprouted?
could we have sprouted?
could you have sprouted?
could they have sprouted? 	could I have been sprouting?
could you have been sprouting?
could she have been sprouting?
could we have been sprouting?
could you have been sprouting?
could they have been sprouting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I sprout?
couldn't you sprout?
couldn't she sprout?
couldn't we sprout?
couldn't you sprout?
couldn't they sprout? 	couldn't I be sprouting?
couldn't you be sprouting?
couldn't she be sprouting?
couldn't we be sprouting?
couldn't you be sprouting?
couldn't they be sprouting? 	couldn't I have sprouted?
couldn't you have sprouted?
couldn't she have sprouted?
couldn't we have sprouted?
couldn't you have sprouted?
couldn't they have sprouted? 	couldn't I have been sprouting?
couldn't you have been sprouting?
couldn't she have been sprouting?
couldn't we have been sprouting?
couldn't you have been sprouting?
couldn't they have been sprouting?