fixes

Author: iliakan

01-recipients-read/solution.md

@@ -40,4 +40,4 @@ messages[0][isRead] = true;
 
 Now third-party code probably won't see our extra property.
 
-Both solutions are possible, though the one with `WeakSet` is "cleaner" from the architectural point of view.
+Although symbols allow to lower the probability of problems, using `WeakSet` is better from the architectural point of view.

01-recipients-read/task.md

@@ -20,4 +20,4 @@ Now, which data structure you could use to store information whether the message
 
 P.S. When a message is removed from `messages`, it should disappear from your structure as well.
 
-P.P.S. We shouldn't modify message objects directly. As they are managed by someone else's code, adding extra properties to them may have bad consequences.
+P.P.S. We shouldn't modify message objects, add our properties to them. As they are managed by someone else's code, that may lead to bad consequences.

02-recipients-when-read/task.md

@@ -17,3 +17,5 @@ let messages = [
 The question now is: which data structure you'd suggest to store the information: "when the message was read?".
 
 In the previous task we only needed to store the "yes/no" fact. Now we need to store the date, and it should only remain in memory until the message is garbage collected.
+
+P.S. Dates can be stored as objects of built-in `Date` class, that we'll cover later.