English verb conjugation
CAN TRAVAIL

Regular verb: travail - travailed - travailed

Affirmation

Simple form	V-ing form
I can travail you can travail he can travail we can travail you can travail they can travail	I can be travailing you can be travailing he can be travailing we can be travailing you can be travailing they can be travailing
Perfect	V-ing perfect
I can have travailed you can have travailed he can have travailed we can have travailed you can have travailed they can have travailed	I can have been travailing you can have been travailing he can have been travailing we can have been travailing you can have been travailing they can have been travailing

Negation

Simple form	V-ing form
I can't travail you can't travail he can't travail we can't travail you can't travail they can't travail	I can't be travailing you can't be travailing he can't be travailing we can't be travailing you can't be travailing they can't be travailing
Perfect	V-ing perfect
I can't have travailed you can't have travailed he can't have travailed we can't have travailed you can't have travailed they can't have travailed	I can't have been travailing you can't have been travailing he can't have been travailing we can't have been travailing you can't have been travailing they can't have been travailing

Interrogative form

Simple form	V-ing form
can I travail? can you travail? can he travail? can we travail? can you travail? can they travail?	can I be travailing? can you be travailing? can he be travailing? can we be travailing? can you be travailing? can they be travailing?
Perfect	V-ing perfect
can I have travailed? can you have travailed? can he have travailed? can we have travailed? can you have travailed? can they have travailed?	can I have been travailing? can you have been travailing? can he have been travailing? can we have been travailing? can you have been travailing? can they have been travailing?

Interro-negative form

Simple form	V-ing form
can't I travail? can't you travail? can't he travail? can't we travail? can't you travail? can't they travail?	can't I be travailing? can't you be travailing? can't he be travailing? can't we be travailing? can't you be travailing? can't they be travailing?
Perfect	V-ing perfect
can't I have travailed? can't you have travailed? can't he have travailed? can't we have travailed? can't you have travailed? can't they have travailed?	can't I have been travailing? can't you have been travailing? can't he have been travailing? can't we have been travailing? can't you have been travailing? can't they have been travailing?