Typo in blocking rules

docs/topic_guides/blocking/blocking_rules.md

@@ -6,7 +6,7 @@ tags:
 
 # What are Blocking Rules?
 
-The primary driver the run time of Splink is the number of record pairs that the Splink model has to process.  This is controlled by the blocking rules.
+The primary driver of Splink's run time is the number of record pairs that the Splink model has to process.  This is controlled by the blocking rules.
 
 This guide explains what blocking rules are, and how they can be used.
 
@@ -140,4 +140,4 @@ It is possible to use more complex blocking rules that use non-equijoin conditio
 l.first_name and r.first_name and levenshtein(l.surname, r.surname) < 3
 ```
 
-However, this will not be executed very efficiently, for reasons described in [this](performance.md) page.
+However, this will not be executed very efficiently, for reasons described in [this](performance.md) page.