Au fait

Are you au fait with the rules of the game?

The Chevalier was, as usual, au fait at all the anecdotes of the court, which had been exceedingly gay, owing to the visit of Madame de Savoie and her daughter, the Princess Marguerite.

Now there is father; he is au fait in all these matters; has a theory for every case of whooping-cough, – and a mission school.

In that case, it would help to have a benevolent deity who is au fait with those complexities — but that there is such a deity is a feature of Stoic theology.

This may sound needless to the professional who is au fait with the history and direction of the investigation.