¿Cuál es la diferencia entre Isn't it because of lack of sleep? y Isn't it for lack of sleep? ?Puedes dar oraciones como ejemplo.

@Joe188 if you want to know the reason for something (for example, why someone has dark eyebags), “Isn’t it for lack of sleep?” is not grammatically correct nor appropriate. You can respond “Isn’t it because of lack of sleep?” though, due to the ‘because’. You would use this if you were skeptical about a person denying their symptoms of sleep deprivation, or if you feel skepticism in general. If someone were taking a medication for lack of sleep, you can respond, “Isn’t it for lack of sleep?” if you two were conversing already. If you were starting that conversation, you would say, “Isn’t that for lack of sleep?” or “Isn’t that to treat sleep deprivation?” (First one is a little more casual).