diff --git a/relational-data.Rmd b/relational-data.Rmd
index 998b96a..c1ce1b6 100644
--- a/relational-data.Rmd
+++ b/relational-data.Rmd
@@ -16,7 +16,7 @@ To work with relational data you need verbs that work with pairs of tables. Ther
 
 * __Set operations__, which treat observations as if they were set elements.
 
-The most common place to find relational data is in a _relational_ database management system (or RDBMS), a term that encompasses almost all modern databases. If you've used a database before, you've almost certainly used SQL. If so, you should find the concepts in this chapter familiar, although their expression in dplyr is a little different. Generally, dplyr is a little easier to use than SQL because dplyr is specialised to do data analysis: it makes common data analysis operations easier, at the expense of making it more difficult to do other things that don't commonly need for data analysis.
+The most common place to find relational data is in a _relational_ database management system (or RDBMS), a term that encompasses almost all modern databases. If you've used a database before, you've almost certainly used SQL. If so, you should find the concepts in this chapter familiar, although their expression in dplyr is a little different. Generally, dplyr is a little easier to use than SQL because dplyr is specialised to do data analysis: it makes common data analysis operations easier, at the expense of making it more difficult to do other things that aren't commonly needed for data analysis.
 
 ### Prerequisites