In English, we often drop adjectives to avoid repeating them. If someone says "Are you furious?", you might simply reply "I am."
In French, you cannot leave a state-of-being verb like être (to be) hanging by itself at the end of a clause. Instead, you must use a pronoun to replace the missing adjective.
To do this, place the neuter object pronoun le directly before the verb. It translates roughly to "so" (as in, "I am so"), though we usually just leave it untranslated in English.
| The boss is furious and I am too. | Le chef est furieux et je le suis aussi. |
| Are you lenient, sir? Yes, I am. | Êtes-vous indulgent, Monsieur ? Oui, je le suis. |
Elision and Invariability
Like other object pronouns, le drops its vowel and becomes l' when the following verb begins with a vowel.
| We are grateful, and I hope that you are too. | Nous sommes reconnaissants, et j'espère que vous l'êtes aussi. |
More importantly, when replacing an adjective, this pronoun is completely invariable. It is always le (or l'), no matter the gender or number of the adjective it is replacing.
Notice in the following examples how it remains unchanged, even when standing in for a plural or feminine adjective:
| You are not exhausted yet, but we are. | Vous n'êtes pas encore épuisés, mais nous le sommes. |
| She is rational and you are too. | Elle est rationnelle et tu l'es aussi. |
Making it Negative
In negative sentences, the pronoun stays glued to the verb. Place ne before the pronoun, and pas after the conjugated verb.
| Are you disappointed? I am not yet. | Es-tu déçu ? Je ne le suis pas encore. |
| It is possible that they are confident, but you are not. | Il est possible qu'ils soient confiants, mais tu ne l'es pas. |
With Other Verbs
While you will see this structure most commonly with être, you can also use le to replace adjectives following other state-of-being verbs, such as devenir (to become) or sembler (to seem).
| He is not indifferent, but it is possible that he becomes so. | Il n'est pas indifférent, mais il est possible qu'il le devienne. |