fix(curriculum): update grammar and tests music 38

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Closes freeCodeCamp#53700

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curriculum/challenges/english/15-javascript-algorithms-and-data-structures-22/learn-basic-string-and-array-methods-by-building-a-music-player/653639d63a45a077333312c8.md

@@ -7,23 +7,26 @@ dashedName: step-38
 
 # --description--
 
-Before playing the song, you need to make sure it starts from the beginning. This can be achieved by the use of the `currentTime` property of the `audio` object. 
+Before playing the song, you need to make sure it starts from the beginning. This can be achieved by the use of the `currentTime` property on the `audio` object. 
 
-Add an `if` statement to check whether the `userData?.currentSong` is `null` or if `userData?.currentSong.id` is strictly not equal `song.id`. Inside `if` block, set the `currentTime` property of the `audio` object to `0`.
+Add an `if` statement to check whether the `userData?.currentSong` is falsy *OR* if `userData?.currentSong.id` is strictly not equal `song.id`. This condition will check if no current song is playing or if the current song is different from the one that is about to be played.
 
+Inside `if` block, set the `currentTime` property of the `audio` object to `0`.
 
 # --hints--
 
-You should create an `if` statement with the condition `userData?.currentSong === null || userData?.currentSong.id !== song.id`.
+Despite the use of the logical *OR* operator, order in this statement is important, as `userData?.currentSong.id` depends on the existence of `userData?.currentSong`.
+
+Don't forget to include optional chaining.
 
 ```js
-assert.match(code, /if\s*\(\s*userData\?\.currentSong\s*===\s*null\s*\|\|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*\)\s*\{\s*/)
+assert.match(code, /if\s*\(\s*(?:(?:!userData\?\.currentSong|\s*userData\?\.currentSong\s*===\s*null)\s*\|\|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*\|\|\s*(?:!userData\?\.currentSong|\s*userData\?\.currentSong\s*===\s*null))\s*\)\s*\{\}/)
 ```
 
 You should set `audio.currentTime` to `0` inside your `if` block.
 
 ```js
-assert.match(code, /if\s*\(\s*userData\?\.currentSong\s*===\s*null\s*\|\|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*\)\s*\{\s*audio\.currentTime\s*=\s*0\s*;?\s*\}/)
+assert.match(code, /if\s*\(\s*(?:(?:!userData\?\.currentSong|\s*userData\?\.currentSong\s*===\s*null)\s*\|\|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*|\s*userData\?\.currentSong\.id\s*!==\s*song\.id\s*\|\|\s*(?:!userData\?\.currentSong|\s*userData\?\.currentSong\s*===\s*null))\s*\)\s*\{\s*audio\.currentTime\s*=\s*0\s*;?\s*\}/)
 ```
 
 # --seed--