diff --git a/src/lib/es5.d.ts b/src/lib/es5.d.ts
index bab3bc67d38..1f352cd6f39 100644
--- a/src/lib/es5.d.ts
+++ b/src/lib/es5.d.ts
@@ -985,7 +985,7 @@ interface ReadonlyArray<T> {
       */
     toString(): string;
     /**
-      * Returns a string representation of an array. The elements are converted to string using thier toLocalString methods.
+      * Returns a string representation of an array. The elements are converted to string using their toLocalString methods.
       */
     toLocaleString(): string;
     /**
@@ -1104,7 +1104,7 @@ interface Array<T> {
       */
     toString(): string;
     /**
-      * Returns a string representation of an array. The elements are converted to string using thier toLocalString methods.
+      * Returns a string representation of an array. The elements are converted to string using their toLocalString methods.
       */
     toLocaleString(): string;
     /**