Then, we create a FOR loop starting at 1, and looping up to the level number.

然后，我们创建一个 FOR 循环，从 1 开始，向上循环到层数。

If the level is not 1, the code inside the ELSE block will be executed instead, and the number of bugs that Grace has to battle is set to 3 times the level number.

如果级别不是 1，则执行 ELSE 块中的代码， 并将 Grace 必须对抗的错误数设置为级别数的 3 倍。