English verb conjugation
CAN GRUMBLE

Regular verb: grumble - grumbled - grumbled

Affirmation

Simple form	V-ing form
I can grumble you can grumble she can grumble we can grumble you can grumble they can grumble	I can be grumbling you can be grumbling she can be grumbling we can be grumbling you can be grumbling they can be grumbling
Perfect	V-ing perfect
I can have grumbled you can have grumbled she can have grumbled we can have grumbled you can have grumbled they can have grumbled	I can have been grumbling you can have been grumbling she can have been grumbling we can have been grumbling you can have been grumbling they can have been grumbling

Negation

Simple form	V-ing form
I can't grumble you can't grumble she can't grumble we can't grumble you can't grumble they can't grumble	I can't be grumbling you can't be grumbling she can't be grumbling we can't be grumbling you can't be grumbling they can't be grumbling
Perfect	V-ing perfect
I can't have grumbled you can't have grumbled she can't have grumbled we can't have grumbled you can't have grumbled they can't have grumbled	I can't have been grumbling you can't have been grumbling she can't have been grumbling we can't have been grumbling you can't have been grumbling they can't have been grumbling

Interrogative form

Simple form	V-ing form
can I grumble? can you grumble? can she grumble? can we grumble? can you grumble? can they grumble?	can I be grumbling? can you be grumbling? can she be grumbling? can we be grumbling? can you be grumbling? can they be grumbling?
Perfect	V-ing perfect
can I have grumbled? can you have grumbled? can she have grumbled? can we have grumbled? can you have grumbled? can they have grumbled?	can I have been grumbling? can you have been grumbling? can she have been grumbling? can we have been grumbling? can you have been grumbling? can they have been grumbling?

Interro-negative form

Simple form	V-ing form
can't I grumble? can't you grumble? can't she grumble? can't we grumble? can't you grumble? can't they grumble?	can't I be grumbling? can't you be grumbling? can't she be grumbling? can't we be grumbling? can't you be grumbling? can't they be grumbling?
Perfect	V-ing perfect
can't I have grumbled? can't you have grumbled? can't she have grumbled? can't we have grumbled? can't you have grumbled? can't they have grumbled?	can't I have been grumbling? can't you have been grumbling? can't she have been grumbling? can't we have been grumbling? can't you have been grumbling? can't they have been grumbling?