C’est and il est can both mean “it is” or “this is” or “he is”. However, they are not synonymous, the use of one expression or the other will depend on what follows.
C’est is a neutral expression used to present someone or something. In that case, it is followed by an article and a noun.
C'est is used in the plural form, ce sont, which means "these are", "those are" or "they are" (not "it is") when followed by an article and a plural.
C’est can also be used to express an opinion about something as a general concept. In that case, it is never in the plural form. It is followed by an adjective in the masculine singular form, even if the idea or thing referred to is feminine or plural.
Il est is masculine singular. In its plural form, it becomes ils sont. It also has a feminine form, elle est in the singular and elles sont in the plural form. It is used to describe someone or something specific.
And of course, il est is also used to indicate the time.
c’est is followed by an article + noun, or an adjective in the masculine singular form.
Il est is followed by an adjective or a profession without article such as le, la, un etc., or is used to express the time.
Complete the sentences using the correct expression c’est/ce sont, il est/elle est/ils sont/elles sont :