ought to skulk
Regular verb: skulk - skulked- skulked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought to skulk
you ought to skulk
she ought to skulk
we ought to skulk
you ought to skulk
they ought to skulk 	I ought to be skulking
you ought to be skulking
she ought to be skulking
we ought to be skulking
you ought to be skulking
they ought to be skulking	I ought to have skulked
you ought to have skulked
she ought to have skulked
we ought to have skulked
you ought to have skulked
they ought to have skulked	I ought to have been skulking
you ought to have been skulking
she ought to have been skulking
we ought to have been skulking
you ought to have been skulking
they ought to have been skulking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I ought not to skulk
you ought not to skulk
she ought not to skulk
we ought not to skulk
you ought not to skulk
they ought not to skulk 	I ought not to skulking
you ought not to skulking
she ought not to skulking
we ought not to skulking
you ought not to skulking
they ought not to skulking	I ought not to have skulked
you ought not to have skulked
she ought not to have skulked
we ought not to have skulked
you ought not to have skulked
they ought not to have skulked	I ought not to have been skulking
you ought not to have been skulking
she ought not to have been skulking
we ought not to have been skulking
you ought not to have been skulking
they ought not to have been skulking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought to I skulk?
ought to you skulk?
ought to she skulk?
ought to we skulk?
ought to you skulk?
ought to they skulk? 	ought to I be skulking?
ought to you be skulking?
ought to she be skulking?
ought to we be skulking?
ought to you be skulking?
ought to they be skulking? 	ought to I have skulked?
ought to you have skulked?
ought to she have skulked?
ought to we have skulked?
ought to you have skulked?
ought to they have skulked? 	ought to I have been skulking?
ought to you have been skulking?
ought to she have been skulking?
ought to we have been skulking?
ought to you have been skulking?
ought to they have been skulking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
ought I not to skulk?
ought you not to skulk?
ought she not to skulk?
ought we not to skulk?
ought you not to skulk?
ought they not to skulk? 	ought I not to be skulking?
ought you not to be skulking?
ought she not to be skulking?
ought we not to be skulking?
ought you not to be skulking?
ought they not to be skulking? 	ought I not to have skulked?
ought you not to have skulked?
ought she not to have skulked?
ought we not to have skulked?
ought you not to have skulked?
ought they not to have skulked? 	ought I not to have been skulking?
ought you not to have been skulking?
ought she not to have been skulking?
ought we not to have been skulking?
ought you not to have been skulking?
ought they not to have been skulking?