In the Thai language, 'จนถึง (jon thǔeng)' is used to denote the limit or extent up to which an action continues or a situation remains. It can be translated to 'until' or 'up to' in English. Generally, it is placed before the noun or time period marking the end point. It can be used with various types of verbs and scenarios to denote duration, extension, or limit of an action or situation.