Agir en or agir comme

Question

How do you say he acted like a king? Il a agi en roi or il a agi comme roi?

Cécile Janty-Davies · Accepted Answer

Bonjour Lucy,
You don't say where you saw this but -
In French, "agir en" and "agir comme" both relate to acting in a certain way, but they're used differently:
Agir en
This means to act in the capacity of or as (in terms of status/role). It emphasizes the official capacity or quality in which someone acts.
Il agit en ami = He acts as a friend / in the capacity of a friend)
Elle a agi en professionnelle = She acted as a professional / in a professional capacity 
Agir en toute conscience = To act consciously/in full awareness
Agir comme
This means to act like or in the manner of. It's more about behaviour, resemblance, or comparison.
Il agit comme un enfant = He acts like a child
 Elle agit comme si elle était la patronne = She acts as if she were the boss
N'agis pas comme ça! = Don't act like that!
 
So to say -
He acted like a king ( assuming he is not a real king!) would be -
Il a agi comme un roi
Hope this helps!