1) The sun was shining warmly at her back as she walked through the park.

2) He felt a chill at his back as the cold wind blew through the alley.

3) The ghostly presence seemed to always be at their backs, watching their every move.

4) With the backpack securely at her back, she set off on the hiking trail.

5) The feeling of unease lingered at his back as he cautiously entered the abandoned house.

6) The sound of footsteps closing in at their back made them quicken their pace.

7) She could sense the predator lurking at her back, ready to strike at any moment.

8) The police officer kept a watchful eye at his back, ensuring his safety in the dangerous neighborhood.

9) The comforting touch of a friend's hand at his back gave him the strength to face his fears.

10) The shadow of the towering mountain loomed ominously at their backs as they continued their trek.