看到蛇时，他吓得往后退了两步。

He ___recoiled in fear when he saw the snake.

她一想到要摸蛇就本能地退缩了。

She instinctively ___recoils at the thought of touching a snake.

这把猎枪后坐力很大，每次射击都会猛烈后退。

The shotgun ___recoils violently with every shot due to its strong kickback.