Learn Italian: Ho visto la donna che origliava il nostro discorso. - I saw the woman eavesdropping on our conversation.

With verbs of perception (like vedere or sentire), Italian often uses a 'pseudo-relative' clause: che + the imperfect indicative. This perfectly captures an action in progress, equivalent to the English '-ing' form. While the infinitive (origliare) is also grammatically correct here, using che origliava strongly emphasizes the ongoing, continuous nature of the eavesdropping at the exact moment she was seen.

Could I use the gerund origliando here, since it literally translates to 'eavesdropping'?

No, and this is a classic trap! In Italian, the gerund almost always refers back to the subject of the main verb. If you said Ho visto la donna origliando, it would actually mean 'I saw the woman while I was eavesdropping.' To describe the object's action, you must use the che + imperfect structure or the infinitive.

Doesn't la donna che origliava just mean 'the woman who was eavesdropping'? How is this different from a normal relative clause?

Grammatically, it looks identical to a standard relative clause. However, in this specific context (perception verb + object + che), it functions as a pseudo-relative clause. The difference is the focus: a normal relative clause identifies the noun ('I saw the woman—the one who was eavesdropping'), while a pseudo-relative clause focuses on perceiving the action itself ('I saw her in the act of eavesdropping'). Context makes the intended meaning clear.

If I wanted to replace la donna with a pronoun ('I saw her eavesdropping'), how would the sentence change?