C’est un livre.
English: This is a book.
In French, 'c’est' and 'ce sont' are used to introduce or identify people or things. They mean 'this is', 'that is', 'these are', or 'those are'.
Use 'c’est' to talk about one person or thing, or to introduce something. Use 'ce sont' when talking about more than one person or thing.
C’est un livre.
English: This is a book.
C’est Marie.
English: This is Marie.
Ce sont des étudiants.
English: These are students.
Ce sont mes amis.
English: These are my friends.
C’est facile.
English: This is easy.