Umberto nunca planea su viaje. su mamá insiste en que umberto planee mejor los viajes. los muchachos no tienen sus tarjetas de embarque. el auxiliar insiste en que ellos las tarjetas antes de abordar.

The word that fill the blank is:

- Umberto nunca planea su viaje. Su mamá insiste en que Umberto planee mejor los viajes. Los muchachos no tienen sus tarjetas de embarque. El auxiliar insiste en que ellos tengan las tarjetas antes de abordar.

Explanation:

The translation of the paragraph is:

- Umberto never plans his trip. His mom insists that Umberto plan trips better. The boys don't have their boarding passes. The attendant insists that they have the cards before boarding.

The whole situation develops when boarding a plane, when Umberto, due to his lack of planning, has forgotten his boarding passes, if you have made a flight you will have noticed that the managers in addition to checking the bags, verify that the passengers have their basic documentation at that time, otherwise they cannot let you pass, it is not that they are bad people or something, they are simply their orders and they must abide by them.