chłopcy

In a sentence

• Chłopcy grają w piłkę na boisku.

  The boys are playing football on the field.

  Here, 'chłopcy' is the subject of the sentence and refers to a group of boys engaging in the activity of playing football.

• Widzę chłopców na ulicy.

  I see boys on the street.

  In this context, 'chłopców' is used as the plural male noun in the accusative case, as they are the direct object of the verb 'see'.

• Rozmawiam z chłopcami o ich projektach.

  I am talking with the boys about their projects.

  Here, 'chłopcami' is in the instrumental case and represents the companions in the action (of talking).