33. The system of claim 20 , further comprising: identifying one or more objects associated with the online social network, each of the identified object corresponding to at least a portion of the text string; accessing the grammar model, wherein the grammar model is a context-free grammar model comprising a plurality of grammars, each grammar comprising one or more tokens; and identifying one or more grammars, each identified grammar having one or more tokens corresponding to at least one of the identified objects.
33. The system of claim 20 , further comprising: identifying one or more objects associated with the online social network, each of the identified object corresponding to at least a portion of the text string; accessing the grammar model, wherein the grammar model is a context-free grammar model comprising a plurality of grammars, each grammar comprising one or more tokens; and identifying one or more grammars, each identified grammar having one or more tokens corresponding to at least one of the identified objects. 34. The system of claim 33 , further comprising: determining a grammar score for each identified grammar; and wherein each suggested query in the set corresponds to an identified grammar having a grammar score greater than a grammar-threshold score, the suggested query being based on a string generated by the identified grammar, each suggested query comprising the tokens of the corresponding identified grammar, wherein one or more of the tokens of the suggested query corresponds to at least one of the identified objects.