Update README.md

Author: tianyin

demo/kube-dev-01-26/README.md

@@ -2,7 +2,7 @@
 
 ## Recap
 
-From the last lecture, we learned to use the Kubernetes built-in resources to deploy the ZooKeeper ensemble. We used Pod resources to deploy ZooKeeper container, and PVC resources to deploy storage. We learned that Kubernetes provides the StatefulSet resource, creating a layer of abstraction over Pods and PVCs.
+We learned to use the Kubernetes built-in resources to deploy the ZooKeeper ensemble. We used Pod resources to deploy ZooKeeper container, and PVC resources to deploy storage. We learned that Kubernetes provides the StatefulSet resource, creating a layer of abstraction over Pods and PVCs.
 
 Remember the State-Reconciliation Principle, where the controller reconciles the system state to match the resources declared in the etcd. For the Pod controller, the **system state** managed by the Pod controller is the containers running in the system. For the PVC controller, the system state is the volumes on the disk.
 
@@ -106,4 +106,4 @@ spec:
   replicas: 5
 ```
 
-**Now try this with the operator you picked!**
+**Now try this with the operator you picked!**