hear sb do sth 听到某人做某事,强调动作的完成.We heard him tell a story.我们听他讲了个故事.
hear sb doing sth 听到某人正在做某事,强调动作正在进行.When I was doing my homework in my study last night,I heard the girl next door singing a song.
所以我觉得
People often hear her sing this song.
She is often heard singing this song.