Hi Berengaria! The verb 'sacrifice' must always be followed by a noun (it's a transitive verb). What are we sacrificing? In this context, it seems to be sleep! So we would say 'I've never sacrificed sleep'. If you are sacrificing something else so that you can sleep, you could say for example: 'I've never sacrificed MY FREE TIME to sleep'. In this sentence, 'my free time' is a phrase behaving as a noun, so it's OK to follow this with 'to sleep' because the preposition 'to' introduces the reason for the sacrifice. Hope this helps!

Sleep is a noun. You have never sacrificed your sleep...just as you have not sacrificed your job, your home or your teddy bear. (Non ho mai sacrificato il sonno) To sleep is a verb. In this sentence 'I have never sacrificed to sleep' would mean 'I have never made a sacrifice in order to be able to sleep.' (Non ho mai sacrificato una cosa per dormire)