She would put off school which set her back a couple of years but she was free to choose and do what she really enjoyed doing.

set 在这里是动词，意思是"使处于某种状态"或"导致某种结果"。 back 在这里是副词，表示"向后"或"返回"的状态。 set back 这个短语动词的意思是"使耽搁/延误"，表示导致某人或某事在进度上落后。在这个句子中，指推迟上学导致她在学业进度上落后了几年。