Answer:
<em>Your question is incomplete. So instead I give you advice on how to identify and understand central ideas in stories. </em>
<em>Explanation:</em>
<em>To “determine a central idea” of a text means to figure out the author's main point or message about a topic.</em>
<em>* Examine the title and any blurbs included before the body of the text.</em>
<em>* Pay close attention to the opening and closing paragraphs.</em>
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First of all, it is important to define preposition phrase in order to find it in this sentence. We can say that "<span>a prepositional phrase will begin with a </span>preposition<span> and will end with a </span>noun<span>, </span>pronoun<span>, </span>gerund<span>, or </span>clause<span>, the "object" of the preposition"
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*In this case, we find UNTIL TODAY as the only prepositional phrase presented. until is the preposition and today is the noun. 
        
                    
             
        
        
        
Formal is like writing to professors. like this, The other day I was with a couple of friends at a cinema. After watching the film the Manager came towards us.... ect ect