diff --git a/episodes/04-quality-control.md b/episodes/04-quality-control.md
index 732d6cdc..5e42cdbd 100644
--- a/episodes/04-quality-control.md
+++ b/episodes/04-quality-control.md
@@ -108,7 +108,7 @@ will group at the ends of the sorted data. Sort your data by each field, one at
 attention to the top and the bottom of a column.
 If your dataset is well-structured and does not contain formulas, sorting should never affect the integrity of your dataset.
 
-**Remember** to expand your sort in order to prevent data corruption. Expanding your sort ensures that the all the data in one row move together instead of only sorting a single column in isolation. Sorting by only a single column will scramble your data - a single row will no longer represent an individual observation.
+**Remember** to expand your sort in order to prevent data corruption. Expanding your sort ensures that all the data in one row move together instead of only sorting a single column in isolation. Sorting by only a single column will scramble your data - a single row will no longer represent an individual observation.
 
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