14. The system of claim 10 wherein creating the plurality of question completion suggestions comprises: generate a set of candidate completion suggestions based on the question prefix and the language model; remove from the set of candidate completion suggestions candidate completion suggestions that do not comply with a set of grammar rules to create a subset of candidate completion suggestions; and filter the subset of candidate completion suggestions based on a filter criteria; and rank the filtered subset.
14. The system of claim 10 wherein creating the plurality of question completion suggestions comprises: generate a set of candidate completion suggestions based on the question prefix and the language model; remove from the set of candidate completion suggestions candidate completion suggestions that do not comply with a set of grammar rules to create a subset of candidate completion suggestions; and filter the subset of candidate completion suggestions based on a filter criteria; and rank the filtered subset. 16. The system of claim 14 wherein the filter criteria selects a candidate completion suggestion based on stored interaction data, the stored interaction data comprising user interactions with prior candidate completion suggestions presented to the user.