Fix some typos in documents (#2592)

Signed-off-by: Xiao An <hac@zju.edu.cn>

3 files changed, 5 insertions, 5 deletions

diff --git a/plugin/etcd/README.md b/plugin/etcd/README.md
index f2dc0f911..6ac267b51 100644
--- a/plugin/etcd/README.md
+++ b/plugin/etcd/README.md
@@ -113,7 +113,7 @@ etcd skydns.local {
 
 Before getting started with these examples, please setup `etcdctl` (with `etcdv3` API) as explained [here](https://coreos.com/etcd/docs/latest/dev-guide/interacting_v3.html). This will help you to put sample keys in your etcd server.
 
-If you prefer, you can use `curl` to populate the `etcd` server, but with `curl` the endpoint URL depends on the version of `etcd`. For instance, `etcd v3.2` or before uses only [CLIENT-URL]/v3alpha/* while `etcd v3.5` or later uses [CLIENT-URL]/v3/* . Also, Key and Value must be base64 encoded in the JSON payload. With, `etcdctl` these details are automatically taken care off. You can check [this document](https://github.com/coreos/etcd/blob/master/Documentation/dev-guide/api_grpc_gateway.md#notes) for details.
+If you prefer, you can use `curl` to populate the `etcd` server, but with `curl` the endpoint URL depends on the version of `etcd`. For instance, `etcd v3.2` or before uses only [CLIENT-URL]/v3alpha/* while `etcd v3.5` or later uses [CLIENT-URL]/v3/* . Also, Key and Value must be base64 encoded in the JSON payload. With `etcdctl` these details are automatically taken care off. You can check [this document](https://github.com/coreos/etcd/blob/master/Documentation/dev-guide/api_grpc_gateway.md#notes) for details.
 
 ### Reverse zones
 
@@ -142,7 +142,7 @@ reverse.skydns.local.
 
 ### Zone name as A record
 
-The zone name itself can be used A record. This behavior can be achieved by writing special entries to the ETCD path of your zone. If your zone is named `skydns.local` for example, you can create an `A` record for this zone as follows:
+The zone name itself can be used as A record. This behavior can be achieved by writing special entries to the ETCD path of your zone. If your zone is named `skydns.local` for example, you can create an `A` record for this zone as follows:
 
 ~~~
 % etcdctl put /skydns/local/skydns/ '{"host":"1.1.1.1","ttl":60}'
@@ -210,4 +210,4 @@ If you query the zone name for `TXT` now, you will get the following response:
 ~~~ sh
 % dig +short skydns.local TXT @localhost
 "this is a random text message."
-~~~
\ No newline at end of file
+~~~
diff --git a/plugin/kubernetes/README.md b/plugin/kubernetes/README.md
index 40d96210a..c2554ffd1 100644
--- a/plugin/kubernetes/README.md
+++ b/plugin/kubernetes/README.md
@@ -208,7 +208,7 @@ or the word "any"), then that label will match all values.  The labels that acce
  * _namespace_ in an `A` record request: service._namespace_.svc.zone, e.g., `nginx.*.svc.cluster.local`
  * _port and/or protocol_ in an `SRV` request: __port_.__protocol_.service.namespace.svc.zone.,
    e.g., `_http.*.service.ns.svc.cluster.local`
- * multiple wild cards are allowed in a single query, e.g., `A` Request `*.*.svc.zone.` or `SRV` request `*.*.*.*.svc.zone.`
+ * multiple wildcards are allowed in a single query, e.g., `A` Request `*.*.svc.zone.` or `SRV` request `*.*.*.*.svc.zone.`
 
  For example, wildcards can be used to resolve all Endpoints for a Service as `A` records. e.g.: `*.service.ns.svc.myzone.local` will return the Endpoint IPs in the Service `service` in namespace `default`:
  ```
diff --git a/plugin/route53/README.md b/plugin/route53/README.md
index 5373e61e8..2711f2564 100644
--- a/plugin/route53/README.md
+++ b/plugin/route53/README.md
@@ -37,7 +37,7 @@ route53 [ZONE:HOSTED_ZONE_ID...] {
 *   `upstream`is used for resolving services that point to external hosts (eg. used to resolve
     CNAMEs). CoreDNS will resolve against itself.
 
-*   `credentials` used for reading the credential file and setting the profile name for a given
+*   `credentials` is used for reading the credential file and setting the profile name for a given
     zone.
 
 *   **PROFILE** AWS account profile name. Defaults to `default`.