I can travel you can travel he can travel we can travel you can travel they can travel
Forma con V-ing
I can be travelling you can be travelling he can be travelling we can be travelling you can be travelling they can be travelling
Perfecto
I can have travelled you can have travelled he can have travelled we can have travelled you can have travelled they can have travelled
Perfecto con V-ing
I can have been travelling you can have been travelling he can have been travelling we can have been travelling you can have been travelling they can have been travelling
Negación
Forma simple
I can't travel you can't travel he can't travel we can't travel you can't travel they can't travel
Forma con V-ing
I can't be travelling you can't be travelling he can't be travelling we can't be travelling you can't be travelling they can't be travelling
Perfecto
I can't have travelled you can't have travelled he can't have travelled we can't have travelled you can't have travelled they can't have travelled
Perfecto con V-ing
I can't have been travelling you can't have been travelling he can't have been travelling we can't have been travelling you can't have been travelling they can't have been travelling
Forma interrogativa
Forma simple
can I travel? can you travel? can he travel? can we travel? can you travel? can they travel?
Forma con V-ing
can I be travelling? can you be travelling? can he be travelling? can we be travelling? can you be travelling? can they be travelling?
Perfecto
can I have travelled? can you have travelled? can he have travelled? can we have travelled? can you have travelled? can they have travelled?
Perfecto con V-ing
can I have been travelling? can you have been travelling? can he have been travelling? can we have been travelling? can you have been travelling? can they have been travelling?
Forma interro-negativa
Forma simple
can't I travel? can't you travel? can't he travel? can't we travel? can't you travel? can't they travel?
Forma con V-ing
can't I be travelling? can't you be travelling? can't he be travelling? can't we be travelling? can't you be travelling? can't they be travelling?
Perfecto
can't I have travelled? can't you have travelled? can't he have travelled? can't we have travelled? can't you have travelled? can't they have travelled?
Perfecto con V-ing
can't I have been travelling? can't you have been travelling? can't he have been travelling? can't we have been travelling? can't you have been travelling? can't they have been travelling?