Something soft moved under her hand and began to grow hard.
She felt him growing hard, and that was exciting, too.
I could see even Arthur's face grow hard as he looked.
It grew hard to recall them all after a while.
I brushed him and he was beginning to grow hard.
We have grown hard in a rough trade, and look it.
She raised the book to obscure the man's face, which grew hard.
Waiting grows hard on those who don't know what's happening.
I could feel him growing hard where he was pressed against my belly.
They grew hard in a second, and he crushed me suddenly against his chest.