Question: I am using Ruby on Rails v3.0.9 and I would like to "transform" an array of strings in a sentence including punctuation. That is, if I have an array like the following:

```
["element 1", "element 2", "element 3"]

```

I would like to get\build:

```
# Note: I added 'Elements are: ' at the begin, ',' between elements and '.' at
# the end.
"Elements are: element 1, element 2, element 3."

```

**How can I do that?**

Answer: 
Rails has `Array#to_sentence` that will do the same as `array.join(', ')` and additionally add "and " before the last item.

```
puts "Elements are: #{["element 1", "element 2", "element 3"].to_sentence}."

```

The rest, as you can see, is just putting it together.
@coreyward's answer is close, but his suggestion's output doesn't match the requested output. This will give you exactly what you want:

```
puts "Elements are: #{array.to_sentence(last_word_connector: ', ')}."

```

See the [docs](http://apidock.com/rails/Array/to_sentence "docs") for more examples and options.