Fix grammar (#14591)

files/en-us/web/css/css_flexible_box_layout/basic_concepts_of_flexbox/index.md

@@ -94,7 +94,7 @@ The live example below has `flex-direction` set to `row-reverse`. Try the other
 
 ## Multi-line flex containers with flex-wrap
 
-While flexbox is a one dimensional model, it is possible to cause our flex items to wrap onto multiple lines. In doing so, you should consider each line as a new flex container. Any space distribution will happen across that line, without reference to the lines either side.
+While flexbox is a one dimensional model, it is possible to cause our flex items to wrap onto multiple lines. In doing so, you should consider each line as a new flex container. Any space distribution will happen across that line, without reference to the lines on either side.
 
 To cause wrapping behavior add the property {{cssxref("flex-wrap")}} with a value of `wrap`. Now, should your items be too large to all display in one line, they will wrap onto another line. The live sample below contains items that have been given a width, the total width of the items being too wide for the flex container. As `flex-wrap` is set to `wrap`, the items wrap. Set it to `nowrap`, which is also the initial value, and they will instead shrink to fit the container because they are using initial flexbox values that allows items to shrink. Using `nowrap` would cause an overflow if the items were not able to shrink, or could not shrink small enough to fit.