Indefinite Pronouns 3

The following indefinite pronouns can be used only and exclusively as pronouns:
Uno/-a, (a person), indicates a single person, but sometimes can be used in the plural:
Ha telefonato uno, che voleva parlarti. <Somebody called who wanted to talk to you.>
Ho ascoltato le opinioni degli uni e degli altri. <I listened to the opinions of different people (the "ones" and the others).>
Qualcuno/qualcuna, <somebody> is used only in the singular.
Qualcuno ha bussato alla porta. <Somebody knocked at the door.>
Ho preparato dei panini. Prendine qualcuno.<I fixed some sandwiches. Have some.>
Ognuno/ognuna <each one/every>, is used only in the singular
Ognuno darà il suo contributo. <Each person will give his/her own contribution.>
Chiunque <anybody, whoever> is only used in the singular and refers only to people.
Chiunque potrebbe farlo. <Anybody could do it.>
Chicchessia <whoever>, used only in the singular, refers only to people.
Non ho paura di chiccessia. <I'm not afraid of anybody.>
Qualcosa <something> is invariable and refers to things in general.
Dimmi qualcosa delle tue vacanze. (Tell me something about your vacation.>
Niente or nulla (nothing), is also invariable.
Non ho paura di niente. <I'm not afraid of anything.> (Notice the use of the double negative )

Thanks
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