1. A method for use in a method for understanding a natural language text, comprising performing the following selectively in a statistical manner: attempting to extract at least one value belonging to a semantic category from a natural language text or a form thereof; and if a result of said attempting complies with a predetermined criterion, attempting to extract, based on said result, at least one value belonging to another semantic category of a different hierarchical level than said semantic category, else performing at least one action from a group of actions including: asking a submitter of said text a question whose content depends on said result and giving up on understanding said natural language text.