What is the difference between 'les' and 'leur'?
"les" is direct object.
"leur" is indirect object (when verb is constructed with "à": je leur parle -> parler à)
What is eux used for then?
"eux" is used as a stressed pronoun, ie as a multiple subject, as an apposition or after a preposition (de, pour, par, sans, avec...):
Can you please clarify? Because I feel that 'them' in this sentence is a direct object.
"Them" is the direct object for "they", and "les" is the direct object for "ils" and "elles".
les = the
leur = their
les = the (article) or them (direct object pronoun)
leur = their (possessive) or them (indirect pronoun)
The phone app didn't let me put the words in the righr order!
Why is "Je les écoute" not marked correct? What is the difference between "écouter" and "entendre"?
"To listen to/écouter" is volunteer, while "to hear/entendre" is not.
Thank you very much, Sitesurf, for your helpful answer.