Ya-t-il des trains pour bruxelles? - oui, il part tous les quarts d'heure. i think it's en in advance.

Hi ! est-ce que vou voulez voyager en france ? (do you want to travel to france ? )b- oui, je veux y voyager. ( yes, i want to travel there)"y" usaually replace a place have to use it in front of the verb to which it refers (here, it's "voyager")"en" is more likely to refers to as "j'en voudrais une part" =" i would like a piece of it""je lui en ai parlé" = i spoke to him/her about itwel, of course, as in french grammar, many exceptions ! hope i !