Catherine:	J’aimerais parler d’un condiment aux usages multiples.
Luc:	C’est un peu vague comme description...
Catherine:	C’est vrai qu’il existe beaucoup de condiments mais il y a autour de celui-ci des légendes très intéressantes liées à l’Histoire de France.
Luc:	Est-ce que tu penses au sel ?

The demonstrative pronouns are used to designate specific nouns. They can have two forms: simple or complex. The complex forms represent the pronouns to which we added the adverbial particles: ci and là.

	Simple Forms		Complex Forms
	Masculine	Feminine	Masculine	Feminine
Singular	celui	celle	celui-ci celui-là	celle-ci celle-là
Plural	ceux	celles	ceux-ci ceux-là	celles-ci celles-là

The Simple Forms:

Celui, celle, ceux, celles, refer to nouns previously mentioned. They agree in gender and number with the nouns they represent. They are always determined by a complement (introduced by the preposition de) or by a relative clause.

For example:

Ne prends pas ma voiture. Prends celle de Marcel.
Don’t take my car; take Marcel’s.

Tu aimes le dessin de Solène ?
Oui, mais je préfère celui de Bruno.
Do you like Solène’s drawing?
Yes, but I prefer Bruno’s.

Vous souvenez-vous des jumelles que nous avons rencontrées au musée ?
Qui ? Celles qui portaient la même robe ?
Non, celles qui avaient la même coupe de cheveux.
Do you remember the twin sisters we met at the museum?
Who? the ones who were wearing the same dress?
No, the ones who had the same haircut.

Tu veux la trotinette en plastique ou celle en métal ?
Do you want the plastic scooter or the metal one?

Il nous reste quelques livres de cuisine mais ceux dont vous parlez ont tous été vendus.
There are some cooking books left, but those you’re talking about have all been sold.

The Complex forms:

Celui-ci,-celui-là, celle-ci, celle-là, ceux-ci, ceux-là, are complex forms of the demonstrative pronouns because they contain the adverbial particles: ci and là. They are usually used to indicate proximity or distance and also opposition.

For example:

Donne-moi ce magazine-là et garde celui-ci pour toi.
Give me that magazine and keep this one for you.

J’aime beaucoup ces tulipes !
Lesquelles ? Celles-ci ou celles-là ?
I love these tulips!
Which ones? these ones or those ones?

Je ne sais pas quelle photo choisir ! Elles sont toutes belles !
Moi, j’aurais choisi celle-ci. Quoique celle-là ne soit pas mal non plus.
Elle montre tous les membres de ta famille !
I don’t know which picture to pick. They are all beautiful!
If I were you, I’d pick this one.
Though that one is not bad either; it shows all your family members!

Tu peux me passer les documents s’il te plaît ?
Ceux-ci ?
Non, ceux-là sur l’étagère.
Can you hand me the documents please?
These ones?
No, those ones on the shelf.

The Neuter or Invariable forms:

The neutral forms: cela, ceci, ça, ce et c’ don’t represent specific nouns. They usually refer to something abstract like an idea or a situation.

Remember: “ c’ ” is used when it’s followed with a vowel (elision).

Ce is very frequently used. It is particularly used as the subject of “être” in the following cases:

To refer to something vague or general, a scene, an idea, the state of something etc...when the predicate following “être” is an adjective.

For example:

C’est beau !
It’s beautiful!

Attention ! C’est chaud !
Be careful! It’s hot!

To refer to “he”, “she”, “it”, or “they” provided that the predicate following the verb “être” is either a noun, a pronoun, a proper noun or a superlative.

For example:

C’est un bon ami.
He is a good friend.

Ce sont ses parents.
They are his parents.

C’est qui ?
C’est Paul.
Who is it?
It’s Paul.

C’est la plus belle maison que j’aie jamais vue !
It’s the most beautiful house I have ever seen!

C’est vraiment difficile. Ce n’est pas de la rigolade !
It’s really hard. It’s not a joke!

C’était une personne que j’aimais bien.
He/She was somebody I liked a lot.

C’est moi !
It’s me!

C’est pas lui qui a cassé le vase. Ce sont eux !
He is not the one who broke the vase. It’s them!

“cela” and “ceci” are used when no emphasis is intended. “Ça” is more used in speaking and in colloquial French than “cela” and “ceci”.

Cela n’a pas de prix. Ça n’a pas de prix.
It’s priceless

Ceci va vous paraître difficile à croire. Ça va vous paraître difficile à croire.
This is going to seem hard for you believe.

Ça m’est égal !
It’s all the same to me!