Describing people precisely

The second entry, affidabile, sits inside a sentence that carries a rule English gives no warning of: cerchiamo qualcuno di affidabile per le chiavi. English sets « somebody » and « reliable » side by side with nothing between them; Italian insists on di. The rule runs across the whole family of indefinite words — qualcuno, qualcosa, niente, nulla — and produces qualcosa di bello, niente di grave, non c’è nulla di nuovo and the everyday question che c’è di strano?. Three things make it worth learning as one block. The adjective after di is always masculine singular, whoever is meant: a woman who fits the description is still qualcuno di affidabile, never qualcuno di affidabila. The preposition changes with what comes next — di before an adjective, da before an infinitive, as in qualcosa da bere and niente da fare. And leaving the di out is not clumsy, it is wrong: cerco qualcuno affidabile is not a sentence anybody would write. Every adjective on this page can stand in that slot, which is why it is worth settling here rather than meeting it thirty times over.