#nullable enable

#region
var (_input, _iter) = (Array.Empty<string>(), 0);
T I<T>() where T : IParsable<T>
{
    while (_iter >= _input.Length) (_input, _iter) = (Console.ReadLine()!.Trim().Split(' '), 0);
    return T.Parse(_input[_iter++], null);
}
#endregion

static bool R(int x1, int y1, int x2, int y2)
{
    if (x1 == x2 || y1 == y2) return true;
    if (x1 - y1 == x2 - y2) return true;
    if (x1 + y1 == x2 + y2) return true;
    return false;
}

void Solve()
{
    var (qx, qy) = (1, 1);
    var (h, w) = (I<int>(), I<int>());
    var (kx, ky) = (I<int>(), I<int>());
    while (kx > 0)
    {
        if (R(qx, qy, kx - 1, ky)) qy = ky;
        qx = kx - 1;
        Console.WriteLine(qx + " " + qy);
        (kx, ky) = (I<int>(), I<int>());
    }
}

for (var t = I<int>(); t > 0; t--) Solve();