Everybody can understand English, it's just a question of finding out how hard you have to shout it. With Zombies it turns you, the answer if very hard. Initial communication with them was hazardous to say the least, and many casualties were suffered trying to find ways of getting close enough and loud enough for them to understand.
Communication was slow, their grunts and growls all sounded the same, and with the death rate of Zombie translators being so high, it was hard to find people qualified and willing to take on the position.
The survivors began to complain, the governments set up within each compound were meeting and discussing plans to shut down Operation Gentleman, and simply got to war with the zombies, and then, suddenly the breakthrough came.
We used radio waves and set it to such a low frequency, like the opposite of a dog whistle.
We started with simple commands like stop, stay where you are, and put the baby down, and it worked, much to all of our surprise.
It didn't take long before we had established a modicum of control over the undead, and the number of casualties during scavenging trips went down, and people were almost able to move around from one community to another, strictly by day you understand. The zombies seemed less willing to cooperate after dark.
It has been almost three years since the disease came, it appeared out of nowhere, and disappeared just as quickly. There were no outbreaks un-related to a direct bite as quick as 4 months after the outbreak began. Our lives have changed, that much is true, but we live them as normally as we can. We live in a state of peace, although I have heard rumours that they are using the radio waves to train the Zombies in combat. I don't know what their plans are, but the compound due east of hear has got some very fertile land that they are growing corn and potatoes in. .... mmm, I could go for some mashed potatoes right about now.