C'_______ (etre)terrible!

(Fill in using the passé composé)
Would the correct answer be "C'est été terrible"?

If it MUST be the passé composé (although l'imparfait looks better!), it is:

être uses avoir = a été but you will NOT begin with C' instead Cela a été. If, however, you MUST begin with C' then it has to be the Imperfect = C'était...

Sra (aka Mme)

est

To correctly form the passé composé with the verb "être" (to be) in French, you need to use the auxiliary verb "être" in the present tense and the past participle of the verb "être".

The past participle of "être" is "été".

Therefore, the correct answer would be: "C'est été terrible."

In this sentence, "C'est" is the contraction of "ce" (this) and "est" (is), and it agrees with the gender and number of the noun it refers to. Additionally, "été" is the past participle of the verb "être" and agrees with the subject (in this case, it remains invariable because "C'est" is an impersonal construction).

To summarize, the correct form of the passé composé with the verb "être" in this sentence is "C'est été terrible."