1. standing or walking站立或步行
Before the teacher finished asking the question, George was on his feet,ready to answer it . 老師的問題還沒問完,喬治就已經站起來準備回答。
How do you keep on your feet so long?你怎麼堅持站了這麼長時間?
2. recovering恢復(身體)
Jack is back on his feet after a long illness. 傑克病了好長時間,現在恢復健康了。