The enemy knew what would happen if they held their ground.
The idea is not to let the enemy know that we're moving.
The enemy would never know who it was that hit him, or why.
The enemy knew who she was, or at least they were pretty sure.
But the enemy as yet do not know if it.
It wouldn't do to have the enemy know she was back, just yet.
That was information any enemy would have known how to use.
There will be no place we can go where the enemy can't know our plans.
We have to stay so the enemy doesn't know we're leaving.
He was positive that his enemy did not know who had called.