In some societies, the term "redhead" is synonymous with hard-headedness, even being mentally challenged.
I put on a mentally challenged accent. “Style is as style does.”
As his IQ drops, he knows he will once again be mentally challenged.
The growing population of elderly persons, the mentally disabled and developmentally challenged will maintain the need for these workers.
But so far, the use of drones has not fundamentally challenged the Geneva Convention-based Law of Armed Conflict.
