docs: fix grammar in docs/running_tests/test_formats

docs/running_tests/test_formats/blockchain_test.md

@@ -28,10 +28,10 @@ For each [`Fixture`](#fixture) test object in the JSON fixture file, perform the
 
     1. Determine whether the current block is valid or invalid:
 
-        1. If the [`expectException`](#-expectexception-transactionexceptionblockexception) field is not present, it is valid, and object must be decoded as a [`FixtureBlock`](#fixtureblock).
-        2. If the [`expectException`](#-expectexception-transactionexceptionblockexception) field is present, it is invalid, and object must be decoded as a [`InvalidFixtureBlock`](#invalidfixtureblock).
+        1. If the [`expectException`](#-expectexception-transactionexceptionblockexception) field is not present, it is valid, and the object must be decoded as a [`FixtureBlock`](#fixtureblock).
+        2. If the [`expectException`](#-expectexception-transactionexceptionblockexception) field is present, it is invalid, and the object must be decoded as an [`InvalidFixtureBlock`](#invalidfixtureblock).
 
-    2. Attempt to decode field [`rlp`](#-rlp-bytes) as the current block
+    2. Attempt to decode the field [`rlp`](#-rlp-bytes) as the current block
         1. If the block cannot be decoded:
             - If an rlp decoding exception is not expected for the current block, fail the test.
             - If an rlp decoding error is expected, pass the test (Note: A block with an expected exception will be the last block in the fixture).
@@ -192,7 +192,7 @@ Root hash of the parent beacon block.
 
 #### - `rlp`: [`Bytes`](./common_types.md#bytes)
 
-RLP serialized version of the block. Field is only optional when embedded in a [`InvalidFixtureBlock`](#invalidfixtureblock) as the [`rlp_decoded`](#-rlp_decoded-optionalfixtureblock) field.
+RLP serialized version of the block. This field is only optional when embedded in an [`InvalidFixtureBlock`](#invalidfixtureblock) as the [`rlp_decoded`](#-rlp_decoded-optionalfixtureblock) field.
 
 #### - `blockHeader`: [`FixtureHeader`](#fixtureheader)
 

docs/running_tests/test_formats/common_types.md

@@ -24,7 +24,7 @@ An empty JSON string `""`, used to represent an empty address. E.g. in the `to`
 
 ### `HeaderNonce`
 
-[Bytes](#bytes) of a 8-byte fixed length.
+[Bytes](#bytes) of an 8-byte fixed length.
 
 ### `HexNumber`
 
@@ -50,7 +50,7 @@ Marks a field as optional, meaning that the field can be missing from the JSON o
 
 ### `ZeroPaddedHexNumber`
 
-Hexadecimal number with "0x" prefix encoded as a JSON string, with a single zero used to pad odd number of digits, and zero represented as "0x00".
+Hexadecimal number with "0x" prefix encoded as a JSON string, with a single zero used to pad an odd number of digits, and zero represented as "0x00".
 
 ## Composite Types
 

repo_subpaths_for_grammar_check.md

@@ -6,7 +6,7 @@ Status legend: `[ ]` pending, `[~]` in progress, `[x]` complete
 
 ## docs/running_tests (~3274 lines total, split into 4 batches)
 
-- [ ] `docs/running_tests/test_formats/common_types.md`, `blockchain_test.md`, `blockchain_test_sync.md` (~920 lines, 3 files)
+- [x] `docs/running_tests/test_formats/common_types.md`, `blockchain_test.md`, `blockchain_test_sync.md` (~920 lines, 3 files)
 - [ ] `docs/running_tests/test_formats/blockchain_test_engine.md`, `blockchain_test_engine_x.md`, `state_test.md`, `transaction_test.md`, `exceptions.md`, `index.md` (~650 lines, 6 files)
 - [ ] `docs/running_tests/consume/**/*.md`, `docs/running_tests/execute/**/*.md` (~950 lines, 10 files)
 - [ ] `docs/running_tests/hive/**/*.md`, `docs/running_tests/*.md` (~750 lines, 10 files)