diff --git a/src/environment.ts b/src/environment.ts
index ce37f6dca518b8e6e862e7278fd3cabda12bfc2c..1ea4ec0a877462e7a858933696f2b7706bdf3dc2 100644
--- a/src/environment.ts
+++ b/src/environment.ts
@@ -18,7 +18,7 @@ function isDefined<T>(x: string, env: Environment<T>): boolean {
 }
 
 function declare<T>(x: string, v: T, env: Environment<T>): void {
-  // 1. Add a variable represented by the parameter `x` into the environment represented by the parameters `env`.
+  // 1. Add a variable represented by the parameter `x` into the environment represented by the parameter `env`.
   // TODO: YOUR CODE HERE // Hint: You can find which methods to use at: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map
 }