As these examples show, the negative is formed by putting non before ne.
Agreement of the past participle
When ne is used with a verb in the present perfect (or any other compound
tense), there are certain rules governing the agreement of the past
participle.
5 When ne is used in a sentence where the quantity is expressed by a number,
the past participle must agree in gender with the noun it replaces, and in
number (i.e. singular or plural) with the quantity of what ne stands for. Take
this question:
In the answer to this question, the ending of comprato will depend on the
gender of rivista (feminine) and on whether you bought one magazine
(singular) or more than one (plural):
The same applies when ne replaces a masculine noun:
Here, the ending of fatto must be masculine, but whether it is singular or
plural will depend on how many exercises have been done:
The same rule applies when the quantity is expressed by qualcuno/qualcuna
(remember that this is always singular) or alcuni/alcune (plural):
‘Hai ancora soldi?’ ‘No, non ne ho
più.’‘Have you still got money?’ ‘No, I’ve
got none left.’Quante riviste hai comprato? How many magazines did you buy?
Ne ho comprata una [fs].
Ne ho comprate due [fp].I bought one.
I bought two.Quanti esercizi [m] avete fatto? How many exercises have
you done?Ne abbiamo fatto uno solo [ms].
Ne abbiamo fatti quattro [mp].We’ve only done one.
We’ve done four.Dovevo fare molti esercizi, ma ne
ho fatto solo qualcuno.
Dovevo fare molti esercizi, ma ne
ho fatti solo alcuni. I was supposed to do a lot of exercises,
but I only did a few.