Querying Best Practices (#796)

* Update website/pages/en/querying/querying-best-practices.mdx

---------

Co-authored-by: Benoît Rouleau <benoit.rouleau@icloud.com>

website/pages/en/querying/querying-best-practices.mdx

@@ -2,15 +2,15 @@
 title: Querying Best Practices
 ---
 
-The Graph provides a decentralized way to query data from blockchains via GraphQL APIs, making it easier to query data with the GraphQL language.
+The Graph provides a decentralized way to query data from blockchains. Its data is exposed through a GraphQL API, making it easier to query with the GraphQL language.
 
-Learn the essential GraphQL language rules and GraphQL querying best practices.
+Learn the essential GraphQL language rules and best practices to optimize your subgraph.
 
 ---
 
 ## Querying a GraphQL API
 
-### The anatomy of a GraphQL query
+### The Anatomy of a GraphQL Query
 
 Unlike REST API, a GraphQL API is built upon a Schema that defines which queries can be performed.
 
@@ -50,7 +50,7 @@ query [operationName]([variableName]: [variableType]) {
 }
 ```
 
-While the list of syntactic do's and don'ts is long, here are the essential rules to keep in mind when it comes to writing GraphQL queries:
+## Rules for Writing GraphQL Queries
 
 - Each `queryName` must only be used once per operation.
 - Each `field` must be used only once in a selection (we cannot query `id` twice under `token`)
@@ -59,17 +59,17 @@ While the list of syntactic do's and don'ts is long, here are the essential rule
 - In a given list of variables, each of them must be unique.
 - All defined variables must be used.
 
-Failing to follow the above rules will end with an error from the Graph API.
+> Note: Failing to follow these rules will result in an error from The Graph API.
 
-For a complete list of rules with code examples, please look at our [GraphQL Validations guide](/release-notes/graphql-validations-migration-guide/).
+For a complete list of rules with code examples, check out [GraphQL Validations guide](/release-notes/graphql-validations-migration-guide/).
 
 ### Sending a query to a GraphQL API
 
 GraphQL is a language and set of conventions that transport over HTTP.
 
 It means that you can query a GraphQL API using standard `fetch` (natively or via `@whatwg-node/fetch` or `isomorphic-fetch`).
 
-However, as stated in ["Querying from an Application"](/querying/querying-from-an-application), it's recommend to use `graph-client` which supports unique features such as:
+However, as mentioned in ["Querying from an Application"](/querying/querying-from-an-application), it's recommended to use `graph-client`, which supports the following unique features:
 
 - Cross-chain Subgraph Handling: Querying from multiple subgraphs in a single query
 - [Automatic Block Tracking](https://github.com/graphprotocol/graph-client/blob/main/packages/block-tracking/README.md)