Added missing word joins.qmd (#1696)

joins.qmd

@@ -581,7 +581,7 @@ We'll come back to non-equi joins in @sec-non-equi-joins.
 
 So far we've explored what happens if a row in `x` matches zero or one row in `y`.
 What happens if it matches more than one row?
-To understand what's going let's first narrow our focus to the `inner_join()` and then draw a picture, @fig-join-match-types.
+To understand what's going on let's first narrow our focus to the `inner_join()` and then draw a picture, @fig-join-match-types.
 
 ```{r}
 #| label: fig-join-match-types