diff --git a/docs/04-certificate-authority.md b/docs/04-certificate-authority.md
index cd02f53..2a29257 100644
--- a/docs/04-certificate-authority.md
+++ b/docs/04-certificate-authority.md
@@ -8,7 +8,7 @@ In this section you will provision a Certificate Authority that can be used to g
 
 Generate the CA configuration file, certificate, and private key:
 
-```
+```sh
 cat > ca-config.json <<EOF
 {
   "signing": {
@@ -62,7 +62,7 @@ In this section you will generate client and server certificates for each Kubern
 
 Generate the `admin` client certificate and private key:
 
-```
+```sh
 cat > admin-csr.json <<EOF
 {
   "CN": "admin",
@@ -103,7 +103,7 @@ Kubernetes uses a [special-purpose authorization mode](https://kubernetes.io/doc
 
 Generate a certificate and private key for each Kubernetes worker node:
 
-```
+```sh
 for instance in worker-0 worker-1 worker-2; do
 cat > ${instance}-csr.json <<EOF
 {
@@ -155,7 +155,7 @@ worker-2.pem
 
 Generate the `kube-controller-manager` client certificate and private key:
 
-```
+```sh
 cat > kube-controller-manager-csr.json <<EOF
 {
   "CN": "system:kube-controller-manager",
@@ -195,7 +195,7 @@ kube-controller-manager.pem
 
 Generate the `kube-proxy` client certificate and private key:
 
-```
+```sh
 cat > kube-proxy-csr.json <<EOF
 {
   "CN": "system:kube-proxy",
@@ -234,7 +234,7 @@ kube-proxy.pem
 
 Generate the `kube-scheduler` client certificate and private key:
 
-```
+```sh
 cat > kube-scheduler-csr.json <<EOF
 {
   "CN": "system:kube-scheduler",
@@ -276,7 +276,7 @@ The `kubernetes-the-hard-way` static IP address will be included in the list of
 
 Generate the Kubernetes API Server certificate and private key:
 
-```
+```sh
 KUBERNETES_PUBLIC_ADDRESS=$(gcloud compute addresses describe kubernetes-the-hard-way \
   --region $(gcloud config get-value compute/region) \
   --format 'value(address)')
@@ -326,7 +326,7 @@ The Kubernetes Controller Manager leverages a key pair to generate and sign serv
 
 Generate the `service-account` certificate and private key:
 
-```
+```sh
 cat > service-account-csr.json <<EOF
 {
   "CN": "service-accounts",
@@ -366,7 +366,7 @@ service-account.pem
 
 Copy the appropriate certificates and private keys to each worker instance:
 
-```
+```sh
 for instance in worker-0 worker-1 worker-2; do
   gcloud compute scp ca.pem ${instance}-key.pem ${instance}.pem ${instance}:~/
 done
@@ -374,7 +374,7 @@ done
 
 Copy the appropriate certificates and private keys to each controller instance:
 
-```
+```sh
 for instance in controller-0 controller-1 controller-2; do
   gcloud compute scp ca.pem ca-key.pem kubernetes-key.pem kubernetes.pem \
     service-account-key.pem service-account.pem ${instance}:~/