How often had she seen that expression on his face before?

I'd seen that expression too often, even if it had been years earlier.

He'd seen that expression before, more times than he could easily count.

You've heard that old expression, to follow one to the ends of the earth.

Not since her parents' loss had she seen that expression.

Once again, he got that very solemn expression on his face.

It's almost - you remember that expression, get the lead out?

But the human had seen that expression on his friend's face before.

She had never seen that particular expression on her mother's face.

He had never seen that expression on her face before.