This sentence contains {ut + subjunctive verb ('emeret')} which is what signals to us that we have a purpose clause. A similar construction is used for a result clause, but we don't have a word saying 'how' something was done (ie an adverb) which would need to be present in the case. Purpose clauses are translated in English as 'in order to'. So, to translate this sentence, first separate the subordinate clause (the one with the 'ut' and the subjunctive verb). Then we can translate each part separately, which will make it easier to see which word belongs where. Answer: the girl was in the forum in order to buy food.For a bonus question, try parsing the two verbs found in the sentence;erat - 3rd person singular imperfect active indicative from 'esse' - 'to be'emeret - 3rd person singular imperfect active subjunctive from 'mere' - 'to buy'