Questions & Answers about Paul est fou.
Est is the third-person singular form of the verb être (to be).
The subject is Paul, which is like he in English, so French uses il est / Paul est.
A quick comparison:
- je suis = I am
- tu es = you are
- il / elle est = he / she is
So:
- Paul est fou = Paul is crazy
Because fou is an adjective, not a noun, in this sentence.
In French, just like in English, after to be / être, you usually use an adjective directly:
- Paul est fou = Paul is crazy
- Marie est heureuse = Marie is happy
You would not say Paul est un fou unless you specifically mean Paul is a madman / a crazy person, where fou is being used as a noun.
So:
- Paul est fou = adjective
- Paul est un fou = noun, different nuance