She's a good friend, but she could also be a very bad enemy.

But in some ways, the test's success has been its own worst enemy.

Think of me as the worst enemy you ever had.

I told him that family members can be your worst enemy once you have money.

How could he have done that to anyone, even his worst enemy?

Sometimes, in this business, success can be your worst enemy.

I have always said give it to your worst enemy.

But those who are your friends will see you as the person they fear most, their worst enemy.

In these cases, natural law's friends have been its worst enemies.

Someone has to do it, because you are your own worst enemy.