Will someone help me with English?

Thanks for viewing my question Yahoo . MedlinePlus Not sure I understand the structure of a sentence below. MedlinePlus ------------------ MedlinePlus A margin call is issued by the clearing house to ensure that a trader can meet future financial obligations if the market moves against you . MedlinePlus ------------------------------------ MedlinePlus ( Quote from a book option trading ) MedlinePlus MedlinePlus I think there must be something lost between obligations and should. Am I correct ? MedlinePlus If I am, what is it? MedlinePlus MedlinePlus In addition , the phrase can be divided into several sentences with each still make sense? MedlinePlus ( For example , you can divide " This is the dog that my dad loves . " In " My dad loves a dog " and " This is the dog." ) MedlinePlus MedlinePlus That way , I would like to see the meaning of the sentence clearer. MedlinePlus MedlinePlus Thanks in advance . :)