请教高手知道我这句话的语法错误

　　请教高手知道我这句话的语法错误。The six representative root samples were collected from different root zones in 38, 70, 92 and 134 days after sowing.
===有问必答===

谢谢你的回答，给我增加了自信，我老感觉自己水平很低！