Update concepts/type-checking/about.md

Co-authored-by: Derk-Jan Karrenbeld <[email protected]>

Author: quintuple-mallard

concepts/type-checking/about.md

@@ -5,7 +5,7 @@ Knowning what the type of a piece of data is, is often very important for code t
 Javascript has several ways to check the type of a value or object.
 
 ```exercism/note
-Javascript's type checking mechanisms are always soomewhat unreliable.
+Javascript's type checking mechanisms can be somewhat unreliable.
 
 For true safety with types, you should probably use TypeScript, a language that builds on JavaScript, but with the type syntax of a static-typed language.
 ```