No hay una explicación lógica porque hay verbos que utilizan preposiciones distintas. Hay que memorizarlas.

Hi Isabel, I have no technical answer. As with every language there is always these verb + preposition combination that you just have to retain. A useful way to remember that is that they also apply to travel: Voy a la oficina (I go to the office) Vengo de la oficina ( I come from the office) Espero te sirva. Saludos!

that is because of the collocations, each verb goes with some prepositions, in this case comenzar a is the same as start to both verbs go with specific prepositions a in Spanish and to in English. the same happens with ¨terminar" wich goes with de: in general there is not a rule we have to learn what prepositions go with the verbs by hard.

Hi, Take the 1st as the beginning of an action/activity/event: "voy a ver una película/ voy a un concierto/voy a ejercitarme". The 2nd as the ending of something: "vengo del cine/ termino de ver una película/vengo del gimnasio/vengo de trabajar". We use a lot of linkers and sometimes you have to feel them right :)

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