"还行"在英语中可以说成 "not bad" 或 "not too bad"。这个短语来自于英语中对于"好"或"不好"的评价。"not bad" 意思是"还不错" 或 "不失"，表示虽然不是特别出色，但是也算是比较好的。
例句：
"How was the movie?" "It was not bad." (电影怎么样？"还行。")
"The food was not too bad, but I've had better." (食物还行，但是我吃过更好的。)
"The book was not bad, but I didn't pke the ending." (这本书还行，但是我不喜欢结局。)