Rails pluralize function comes in handy when you need to differentiate "1 person" and "2 people" based on users count. You could just simply do:

pluralize(users.count, 'person')

If you don't want the number shows up, you could do:

'person'.pluralize(users.count)

When users.count == 1, it returns "person", and users.count == 2 => "people"

Now expand that to generate a sentence of "xx person/people is/are going". One way of doing that is through application helper. A helper function is defined as:

def sentence_pluralize(num)
  if num == 1
    "1 person is going"
  else
    "#{num} people are going"
  end
end

Then you could call that from anywhere in the application to get the correct sentence.

There is another way to achieve this. First add a customer inflection in config/initializers/inflections.rb to pluralize "is"/"are"

ActiveSupport::Inflector.inflections do |inflect|
  inflect.irregular "is", "are"
end

Now let's put these pieces together. We get "xx person/people" by

pluralize(users.count, 'person')

Then get "is"/"are" (without the number) by

'is'.pluralize(users.count)

In our mockup we have:

<div>
  <%=pluralize(users.count, 'person') %> 
  <%='is'.pluralize(users.count) %>
  going
</div>

It gets what we want.