fix(guides) Fixed gramattical error (#2477)

* Update code-splitting.md

* Update code-splitting.md

src/content/guides/code-splitting.md

@@ -321,8 +321,8 @@ T> webpack will add the prefetch hint once the parent chunk has been loaded.
 
 Preload directive has a bunch of differences compared to prefetch:
 
-- A preloaded chunk starts loading in parallel to the parent chunk. A prefetched chunk starts after the parent chunk finish.
-- A preloaded chunk has medium priority and instantly downloaded. A prefetched chunk is downloaded in browser idle time.
+- A preloaded chunk starts loading in parallel to the parent chunk. A prefetched chunk starts after the parent chunk finishes loading.
+- A preloaded chunk has medium priority and is instantly downloaded. A prefetched chunk is downloaded while browser is idle.
 - A preloaded chunk should be instantly requested by the parent chunk. A prefetched chunk can be used anytime in the future.
 - Browser support is different.