I can letch you can letch he can letch we can letch you can letch they can letch
Forme en V-ing
I can be letching you can be letching he can be letching we can be letching you can be letching they can be letching
Perfect
I can have letched you can have letched he can have letched we can have letched you can have letched they can have letched
Perfect en V-ing
I can have been letching you can have been letching he can have been letching we can have been letching you can have been letching they can have been letching
Négation
Forme simple
I cannot letch you cannot letch he cannot letch we cannot letch you cannot letch they cannot letch
Forme en V-ing
I cannot be letching you cannot be letching he cannot be letching we cannot be letching you cannot be letching they cannot be letching
Perfect
I cannot have letched you cannot have letched he cannot have letched we cannot have letched you cannot have letched they cannot have letched
Perfect en V-ing
I cannot have been letching you cannot have been letching he cannot have been letching we cannot have been letching you cannot have been letching they cannot have been letching
Forme interrogative
Forme simple
can I letch? can you letch? can he letch? can we letch? can you letch? can they letch?
Forme en V-ing
can I be letching? can you be letching? can he be letching? can we be letching? can you be letching? can they be letching?
Perfect
can I have letched? can you have letched? can he have letched? can we have letched? can you have letched? can they have letched?
Perfect en V-ing
can I have been letching? can you have been letching? can he have been letching? can we have been letching? can you have been letching? can they have been letching?
Forme interro-négative
Forme simple
can I not letch? can you not letch? can he not letch? can we not letch? can you not letch? can they not letch?
Forme en V-ing
can I not be letching? can you not be letching? can he not be letching? can we not be letching? can you not be letching? can they not be letching?
Perfect
can I not have letched? can you not have letched? can he not have letched? can we not have letched? can you not have letched? can they not have letched?
Perfect en V-ing
can I not have been letching? can you not have been letching? can he not have been letching? can we not have been letching? can you not have been letching? can they not have been letching?