merge, minor: typo fixes

Author: Sam Kleinman

source/reference/command/removeShard.txt

@@ -14,7 +14,7 @@ removeShard
 
       { removeShard : "[shardName]" }
 
-   The balancer will then migrating chunks from the shard specified by
+   The balancer will then migrate chunks from the shard specified by
    ``[shardName]``. This process happens slowly to avoid placing
    undue load on the overall cluster.
 
@@ -36,7 +36,7 @@ removeShard
    to list the databases that you must move from the shard.
 
    Each database in a sharded cluster has a primary shard. If the
-   shard you want to remove is also the primary of one the cluster's
+   shard you want to remove is also the primary of one of the cluster's
    databases, then you must manually move the database to a new
    shard. This can be only after the shard is empty. See the
    :dbcommand:`movePrimary` command for details.