Proof that cloning a dictionary with MemberwiseClone is bad...

void Main()
{
    var original = new BadDict<string, int> { { "a", 1 } };
    var clone = original.Clone();
    Console.WriteLine (clone["a"]); // 1, OK
    Console.WriteLine (original["a"]); // 1, OK

    clone["a"] = 42;
    Console.WriteLine (clone["a"]); // 42, OK
    Console.WriteLine (original["a"]); // 42, oops !

}

class BadDict<K,V> : Dictionary<K,V>
{
    public BadDict<K,V> Clone()
    {
        return (BadDict<K,V>)MemberwiseClone();
    }
}