can travel
Regular verb: travel - travelled- travelled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I can travel
you can travel
she can travel
we can travel
you can travel
they can travel 	I can be travelling
you can be travelling
she can be travelling
we can be travelling
you can be travelling
they can be travelling	I can have travelled
you can have travelled
she can have travelled
we can have travelled
you can have travelled
they can have travelled	I can have been travelling
you can have been travelling
she can have been travelling
we can have been travelling
you can have been travelling
they can have been travelling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I cannot travel
you cannot travel
she cannot travel
we cannot travel
you cannot travel
they cannot travel 	I cannot be travelling
you cannot be travelling
she cannot be travelling
we cannot be travelling
you cannot be travelling
they cannot be travelling	I cannot have travelled
you cannot have travelled
she cannot have travelled
we cannot have travelled
you cannot have travelled
they cannot have travelled	I cannot have been travelling
you cannot have been travelling
she cannot have been travelling
we cannot have been travelling
you cannot have been travelling
they cannot have been travelling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I travel?
can you travel?
can she travel?
can we travel?
can you travel?
can they travel? 	can I be travelling?
can you be travelling?
can she be travelling?
can we be travelling?
can you be travelling?
can they be travelling? 	can I have travelled?
can you have travelled?
can she have travelled?
can we have travelled?
can you have travelled?
can they have travelled? 	can I have been travelling?
can you have been travelling?
can she have been travelling?
can we have been travelling?
can you have been travelling?
can they have been travelling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
can I not travel?
can you not travel?
can she not travel?
can we not travel?
can you not travel?
can they not travel? 	can I not be travelling?
can you not be travelling?
can she not be travelling?
can we not be travelling?
can you not be travelling?
can they not be travelling? 	can I not have travelled?
can you not have travelled?
can she not have travelled?
can we not have travelled?
can you not have travelled?
can they not have travelled? 	can I not have been travelling?
can you not have been travelling?
can she not have been travelling?
can we not have been travelling?
can you not have been travelling?
can they not have been travelling?