3 files changed, 21 insertions, 8 deletions
diff --git a/guides/source/active_record_migrations.md b/guides/source/active_record_migrations.md
index ad069a112e..0b84001ca5 100644
--- a/guides/source/active_record_migrations.md
+++ b/guides/source/active_record_migrations.md
@@ -423,21 +423,23 @@ change_column :products, :part_number, :text
 ```
 
 This changes the column `part_number` on products table to be a `:text` field.
+Note that `change_column` command is irreversible.
 
 Besides `change_column`, the `change_column_null` and `change_column_default`
-methods are used specifically to change a not null constraint and default values of a
-column.
+methods are used specifically to change a not null constraint and default
+values of a column.
 
 ```ruby
 change_column_null :products, :name, false
-change_column_default :products, :approved, false
+change_column_default :products, :approved, from: true, to: false
 ```
 
 This sets `:name` field on products to a `NOT NULL` column and the default
-value of the `:approved` field to false.
+value of the `:approved` field from true to false.
 
-TIP: Unlike `change_column` (and `change_column_default`), `change_column_null`
-is reversible.
+Note: You could also write the above `change_column_default` migration as
+`change_column_default :products, :approved, false`, but unlike the previous
+example, this would make your migration irreversible.
 
 ### Column Modifiers
 
diff --git a/guides/source/association_basics.md b/guides/source/association_basics.md
index 5c96a53d09..c0fa3cfd04 100644
--- a/guides/source/association_basics.md
+++ b/guides/source/association_basics.md
@@ -1519,20 +1519,30 @@ conditions exists in the collection. It uses the same syntax and options as
 
 ##### `collection.build(attributes = {}, ...)`
 
-The `collection.build` method returns one or more new objects of the associated type. These objects will be instantiated from the passed attributes, and the link through their foreign key will be created, but the associated objects will _not_ yet be saved.
+The `collection.build` method returns a single or array of new objects of the associated type. The object(s) will be instantiated from the passed attributes, and the link through their foreign key will be created, but the associated objects will _not_ yet be saved.
 
 ```ruby
 @order = @customer.orders.build(order_date: Time.now,
                                 order_number: "A12345")
+
+@orders = @customer.orders.build([
+  { order_date: Time.now, order_number: "A12346" },
+  { order_date: Time.now, order_number: "A12347" }
+])
 ```
 
 ##### `collection.create(attributes = {})`
 
-The `collection.create` method returns a new object of the associated type. This object will be instantiated from the passed attributes, the link through its foreign key will be created, and, once it passes all of the validations specified on the associated model, the associated object _will_ be saved.
+The `collection.create` method returns a single or array of new objects of the associated type. The object(s) will be instantiated from the passed attributes, the link through its foreign key will be created, and, once it passes all of the validations specified on the associated model, the associated object _will_ be saved.
 
 ```ruby
 @order = @customer.orders.create(order_date: Time.now,
                                  order_number: "A12345")
+
+@orders = @customer.orders.create([
+  { order_date: Time.now, order_number: "A12346" },
+  { order_date: Time.now, order_number: "A12347" }
+])
 ```
 
 ##### `collection.create!(attributes = {})`
diff --git a/guides/source/getting_started.md b/guides/source/getting_started.md
index 79d4393f32..a091f84fb0 100644
--- a/guides/source/getting_started.md
+++ b/guides/source/getting_started.md
@@ -298,6 +298,7 @@ Rails.application.routes.draw do
 
   # The priority is based upon order of creation:
   # first created -> highest priority.
+  # See how all your routes lay out with "rake routes".
   #
   # You can have the root of your site routed with "root"
   # root 'welcome#index'