```ruby
class Phone < ActiveRecord::Base

  belongs_to :user

  enum kind: {home: 0, work: 1, cell: 2}

  validates :kind, :number, presence: true

end
```

Rename home to evening and work to daytime and make daytime default.
user
```ruby
class Phone < ActiveRecord::Base

  belongs_to :user

  enum kind: {daytime: 0, evening: 1, cell: 2}

  validates :kind, :number, presence: true

end
```
assistant