Even smart folks become absent-minded at times.

He lived idly and found himself already forty years old.

He was idly turning over the page of a magazine.

He wore a blank look.

The fat woman, the young couple, the sleeping Indian and the tall man in black, but now skin and flesh and hair had disappeared, and empty eye sockets stared from gleaming white skulls.

If you drive carelessly, you will miss your turn.

Don't look away idly; just pay attention to what you're doing.

If you didn't have your head in the clouds, you could succeed.

Jim is what is called an absent-minded student.

The fact is apparent to the most casual observer.