Fix grammar (#43008)

Fixes anonymous feedback issue.

Author: BillWagner

docs/csharp/language-reference/statements/lock.md

@@ -10,7 +10,7 @@ helpviewer_keywords:
 ---
 # The lock statement - ensure exclusive access to a shared resource
 
-The `lock` statement acquires the mutual-exclusion lock for a given object, executes a statement block, and then releases the lock. While a lock is held, the thread that holds the lock can again acquire and release the lock. Any other thread is blocked from acquiring the lock and waits until the lock is released. The `lock` statement ensures that at maximum only one thread executes its body at any time moment.
+The `lock` statement acquires the mutual-exclusion lock for a given object, executes a statement block, and then releases the lock. While a lock is held, the thread that holds the lock can again acquire and release the lock. Any other thread is blocked from acquiring the lock and waits until the lock is released. The `lock` statement ensures that at maximum only one thread executes its body at any moment in time.
 
 The `lock` statement takes the following form: