英语短文改错 The Milu deer used to be common in China long before.As other deer they

题目

英语短文改错 The Milu deer used to be common in China long before.As other deer they
lived together and eat grass and soft parts of trees such as small branch.
问：long before 里面的before 为什么 要变成ago .as 为什么变成like?

答案