weakly

The injured hiker waved weakly at the rescue helicopter as it circled overhead.

(Chinese) 受伤的徒步旅行者向在头顶盘旋的救援直升机无力地挥了挥手。

He smiled weakly from his hospital bed, still too tired to speak for more than a minute.

(Chinese) 他在病床上虚弱地笑了笑，累得连说话都坚持不了一分钟。