The difficulty in using C'est or Il est is that often they may have the same translation in English: It is or This is. Therefore it is very important to learn carefully the well defined rule which applies to the use of C'est or Il est (and their related forms Ce sont and Elle est/Ils sont/Elles sont).
C'est and Ce sont are used with a noun (or a proper name) and Il est/Elle est/Ils sont/Elles sont are used with an adjective. Look at the example below:
C'est un livre.^4 Il est intΘressant.
C'est + noun^4 Il est + adjective
(It is a book)^4 (It is interesting)
The same is true in the plural.
Ce sont des livres.^4 Ils sont intΘressants.
Ce sont + noun^4 Ils sont + adjective
(These are books)^4 (They are interesting)
This simple rules seems to be getting complicated sometimes but it really is not.
1. Il est (and related forms) can be followed by nouns expressing nationality, profession, national origin, or religious preference. In this case, these nouns are used without an article and are considered adjectives. So you are still following the original rule (Il est + adjective). Obviously you can use the nouns expressing nationality, profession, national origin, or religious preference with an article after c'est! Contrast the following sentences:
C'est un Franτais^4 Il est franτais.
(He is French / a Frenchman)^4 (He is French / a Frenchman)
Ce sont des Θtudiantes.^4 Elles sont Θtudiantes.
(They are female students)^4 (They are female students)
Note that as a noun the noun of nationality (Franτais) is capitalized and that the adjective of nationality (franτais) is not capitalized, as is always the case in French.
2. C'est can be followed by an adjective. This adjective can only be used in the masculine singular. In this case, c'est + adjectif can only refer to a general idea. It can never refer or talk about somebody or something specific. Contrast the following sentences:
J'Θtudie le franτais.^4 C'est important.
(I study French)^4 (It is important)
C'est le prΘsident de la banque.^4 Il est important.
(This/He is the president of the bank)^4 (He is important)
C'est la directrice du musΘe^4 Elle est importante
(This/She is the director of the museum)^4 (She is important)
This rule only applies to C'est. It is not possible for Ce sont to be followed by an adjective.
Descriptive adjectives.
Descriptive adjectives modify nouns. Whenever you use an adjective in French, you must remember to make sure that it agrees in gender and number with the noun it modifies. To make most adjectives change gender (masculine or feminine) and/or number (singular or plural) follow this simple rule:
masculine becomes feminine by adding a final -e
singular becomes plural by adding a final -s
^3 SINGULAR^5 PLURAL
MASCULINE^3 intΘressant^5 intΘressant{s}
FEMININE^3 intΘressant{e}^5 intΘressant{es}
In French, there are also irregular adjectives. This means that their rule of agreement is different from the one above. Here is a list of the most common irregular adjectives and their agreement:
If you are not sure whether an adjective is regular or not, look it up in a dictionary.
Some adjectives have more than one form in the masculine singular
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In English, the majority of adjectives are placed in front of the nouns they modify. In French the majority of adjectives are placed `after `the `nouns they modify. The most common adjectives which come before the noun they modify are:
beau
bon^2 mauvais
grand^2 petite
jeune^2 vieux
joli
nouveau
If you need to use two adjectives in front of a noun or two adjectives after a noun, use `et (and) between them:
Cette recette est longue et difficile.
(This recipe is long and difficult)
A few French adjectives change meaning depending on their position:
