add more contents, refine some sentences

BEPs/BEP322.md

@@ -30,8 +30,8 @@ economic considerations for real adoptions.
 
 ## 2. Motivation
 
-The specification is defined in [Ethereum Builder API
-Specification](https://github.com/ethereum/builder-specs), and it has been supported by almost all the mainstream
+The [Ethereum Builder API
+Specification](https://github.com/ethereum/builder-specs) has been supported by almost all the mainstream
 Ethereum consensus clients. Nowadays, the inclusion rate of blocks from builders
 is [about 90%](https://dune.com/ChainsightAnalytics/mev-after-ethereum-merge) (based on the statistics of October 2023).
 
@@ -60,9 +60,8 @@ as bring new benefits for the ecosystem.
 ### 3.1 BSC Trust Model
 
 Before we move on to the design of Builder Specification, let's have an
-analysis of the BSC trust model and compare it to Ethereum, for it will
-affect how the design works and differentiate the designs in these two
-networks.
+analysis of the BSC trust model and compare it to Ethereum. It will
+lead to different designs for these two networks.
 
 - Validators are more trustworthy in BNB Smart Chain. In BSC, the
   validators should delegate a lot of BNB (more than 10 thousand in
@@ -116,6 +115,10 @@ The overall workflow is as follows:
     timeout to retrieve transitions from the builder, or the proposed
     block is invalid).
 
+For step 4, a builder can also submit a bid with transactions, then at step 7 a proposer
+does not need to ask for transactions and can send the receipt in an asynchronous way.
+This option is also supported in this specification.
+
 Here, we would like to highlight some main differences between Ethereum
 Builder Specification here for the readers who are familiar with it.
 
@@ -171,8 +174,8 @@ timeout to retrieve transactions from the winning builder.
 
 ![block timing](./assets/bep-322/block_timing.png)
 
-Secondly, a validator can choose to participate in or not. The
-implementation should support a validator to turn on/off the feature
+Secondly, a validator can choose to run a node with or without support for builder.
+The implementation should support a validator to turn on/off the feature
 based on its choice.
 
 ### 3.3 Payment & Economic Considerations
@@ -401,7 +404,7 @@ api is timeout-ed, a validator can notify the builder.
 <table>
 <tr>
 <td>Path</td> 
-<td>/bsc/v1/builder/issues</td>
+<td>/bsc/v1/builder/issue</td>
 </tr>
 
 <tr>