I tried to pull my hand away, but his grip tightened.
She tried to move away and his grip tightened, but only enough to hold her.
I made an attempt to free my hand, and his grip tightened.
She started to pull her hand away, but his grip tightened.
Her grip tightened on his hand as though she would never let go.
She would have pulled her hand away, but his grip tightened.
I tried to pull my hands free, and his grip tightened.
Her grip on his arm tightened for a second, then she was gone into the night.
His grip tightened on my arms, and I turned to look at him.
His grip only tightened when she would have pulled away.