Hot answers tagged preposiciones
You can use "en" when using "at" as inside a building. ¿Por qué estás en mi casa? (the subject "tu" (you) is hidden in this phrase as it can be understood from context). The proposition "a" implies direction, me voy a casa -> I'm going home The proposition "de" implies relation or posession. salgo de casa -> I'm leaving home la casa ...
"Clamar" can either be transitive or intransitive, having slightly different meanings, and with each you would use different prepositions. Among these meanings would be: demand, clamor for, complain, call out and cry out (for). The sentence you took as an example could thus have different meanings depending on how we use the prepositions (like contra) or ...
A dictionary should help :) As WordReference shows (click on the Collins tab), clamar contra means to protest against, cry out against. Regarding al, "al" + infinitive means "when". Al recordar is somewhat translatable as when remembering. See this answer.
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