English verb conjugation
CAN UNDULATE

Regular verb: undulate - undulated - undulated

Affirmation

Simple form	V-ing form
I can undulate you can undulate he can undulate we can undulate you can undulate they can undulate	I can be undulating you can be undulating he can be undulating we can be undulating you can be undulating they can be undulating
Perfect	V-ing perfect
I can have undulated you can have undulated he can have undulated we can have undulated you can have undulated they can have undulated	I can have been undulating you can have been undulating he can have been undulating we can have been undulating you can have been undulating they can have been undulating

Negation

Simple form	V-ing form
I can't undulate you can't undulate he can't undulate we can't undulate you can't undulate they can't undulate	I can't be undulating you can't be undulating he can't be undulating we can't be undulating you can't be undulating they can't be undulating
Perfect	V-ing perfect
I can't have undulated you can't have undulated he can't have undulated we can't have undulated you can't have undulated they can't have undulated	I can't have been undulating you can't have been undulating he can't have been undulating we can't have been undulating you can't have been undulating they can't have been undulating

Interrogative form

Simple form	V-ing form
can I undulate? can you undulate? can he undulate? can we undulate? can you undulate? can they undulate?	can I be undulating? can you be undulating? can he be undulating? can we be undulating? can you be undulating? can they be undulating?
Perfect	V-ing perfect
can I have undulated? can you have undulated? can he have undulated? can we have undulated? can you have undulated? can they have undulated?	can I have been undulating? can you have been undulating? can he have been undulating? can we have been undulating? can you have been undulating? can they have been undulating?

Interro-negative form

Simple form	V-ing form
can't I undulate? can't you undulate? can't he undulate? can't we undulate? can't you undulate? can't they undulate?	can't I be undulating? can't you be undulating? can't he be undulating? can't we be undulating? can't you be undulating? can't they be undulating?
Perfect	V-ing perfect
can't I have undulated? can't you have undulated? can't he have undulated? can't we have undulated? can't you have undulated? can't they have undulated?	can't I have been undulating? can't you have been undulating? can't he have been undulating? can't we have been undulating? can't you have been undulating? can't they have been undulating?