Questions & Answers about האף שלי סתום, ולכן אני לא יכולה לישון טוב.
Because Hebrew often uses the definite article ה־ with a possessed noun when you mean a specific thing, like my nose.
So:
- האף שלי = my nose / the nose of mine
- אף שלי would sound less natural here
With body parts, the definite form is especially common, because you are usually talking about one specific, known thing.
Here, האף is pronounced roughly ha-af.
- אף = nose
- האף = the nose
A learner may also notice that אף can mean something else in other contexts, like even or also not in more formal/literary Hebrew. But in this sentence, because of the context and the definite article ה־, it clearly means nose.