"She is a girl and she is calm."
Translation:C'est une fille et elle est calme.
When describing people and things with être in French, you usually can't use a personal subject pronoun like elle. Instead, you must use the impersonal pronoun ce, which can also mean "this" or "that".
These pronouns aren't interchangeable. The basic rule is that you must use ce when être is followed by any determiner—for instance, an article (as it is in this sentence → "She is a girl") or a possessive adjective. Hence, C'est une fille.
If an adjective, adverb, or both appear after être, as is the case with "she is calm", then use the personal pronoun → elle est calme.
I suppose a lot of confusion is stemming from the fact that Duolingo, in earlier french lessons, told us it was acceptable to say 'Elle est une fille' or 'Il est un garçon' but now seems to be going back on it. Should I use Ce or C' in all situations with est un or est une?
Yes. The rule is that "il/elle est" and "ils/elles sont" change to "c'est" and "ce sont" before a modified noun, that is, a noun preceded by a modifier. A modifier can be:
- an article: un, une, des, le, la, l', les
- a number: un, deux...
- a possessive adjective: mon, ton, son, ma, ta, sa, notre, votre, leur, mes, tes, ses, nos, vos, leurs
- a demonstrative adjective: ce, cet, cette, ces
These articles go into more detail and are worth a read.
Also, the Tips and Notes for the Gallicism skill (click the lightbulb icon when you open the skill) give more information.
If you are using c'/ce wouldn't the sentence translate more accurately to "this girl" rather than she is a girl
You can't translate French too literally into English, it will mess you up.
'Ce' is an impersonal pronoun in French, so when used in the context of this sentence, it still is 'she'.
Is jeune fille incorrect? Google translate gives it as an alternative to fille.