'etc' should be 'etc.'

Signed-off-by: YuPengZTE <yu.peng36@zte.com.cn>

docs/getting-started-guides/rackspace.md

@@ -62,7 +62,7 @@ There is a specific `cluster/rackspace` directory with the scripts for the follo
 ## Network Design
 
 - eth0 - Public Interface used for servers/containers to reach the internet
-- eth1 - ServiceNet - Intra-cluster communication (k8s, etcd, etc) communicate via this interface. The `cloud-config` files use the special CoreOS identifier `$private_ipv4` to configure the services.
+- eth1 - ServiceNet - Intra-cluster communication (k8s, etcd, etc.) communicate via this interface. The `cloud-config` files use the special CoreOS identifier `$private_ipv4` to configure the services.
 - eth2 - Cloud Network - Used for k8s pods to communicate with one another. The proxy service will pass traffic via this interface.
 
 ## Support Level

docs/getting-started-guides/scratch.md

@@ -72,7 +72,7 @@ accomplished in two ways:
     pod network through traffic encapsulation (e.g vxlan).
   - Encapsulation reduces performance, though exactly how much depends on your solution.
 - **Without an overlay network**
-  - Configure the underlying network fabric (switches, routers, etc) to be aware of pod IP addresses.
+  - Configure the underlying network fabric (switches, routers, etc.) to be aware of pod IP addresses.
   - This does not require the encapsulation provided by an overlay, and so can achieve 
     better performance.
 

docs/user-guide/jobs.md

@@ -157,7 +157,7 @@ parallelism, for a variety or reasons:
   remaining completions.   Higher values of `.spec.parallelism` are effectively ignored.
 - For work queue jobs, no new pods are started after any pod has succeeded -- remaining pods are allowed to complete, however.
 - If the controller has not had time to react.
-- If the controller failed to create pods for any reason (lack of ResourceQuota, lack of permission, etc),
+- If the controller failed to create pods for any reason (lack of ResourceQuota, lack of permission, etc.),
   then there may be fewer pods than requested.
 - The controller may throttle new pod creation due to excessive previous pod failures in the same Job.
 - When a pod is gracefully shutdown, it make take time to stop.

docs/user-guide/volumes.md

@@ -485,7 +485,7 @@ spec:
 
 ## Resources
 
-The storage media (Disk, SSD, etc) of an `emptyDir` volume is determined by the
+The storage media (Disk, SSD, etc.) of an `emptyDir` volume is determined by the
 medium of the filesystem holding the kubelet root dir (typically
 `/var/lib/kubelet`).  There is no limit on how much space an `emptyDir` or
 `hostPath` volume can consume, and no isolation between containers or between