绑定不匹配:类型不是该类型的有界参数<E>>的有效替代项

我有一门课:

public class BinarySearchTree<E extends Comparable<E>> {
    private TreeNode<E> root;
    //other methods like insert, etc
}

public class TreeNode<V extends Comparable<V>> implements Comparable<V>{
    //left and right instances of TreeNode and data holder V instance. 
    //insert method, etc
    @Override
    public int compareTo(V o) {
        return 0;
    }
}

当我在课堂上用 BinarySearchTree ,:

public void levelOrderTraversalQueue() {
    Queue<TreeNode<E>> q = new Queue(); //<--Bound mismatch: The type BinarySearchTree<E>.TreeNode<E> is not a valid substitute for the bounded parameter <E extends Comparable<E>> of the type Queue<E>
}

为什么?我的队列类实现如下:

public class Queue<E extends Comparable<E>> {
    private LinkedList<E> list;
    //other operations
}

如何解决此错误?