Phrases that have a dependency relationship with another sentence within the same sentence are called subordinate clauses. in other words we can affirm that these clauses do not have complete thought and need another phrase so that the reader can establish a reasoning. Subordinated Clauses may exercise the function of essential terms, members or accessories of the sentence.
One reason my school has been excelling in academic work is that the kid's are respectful, second of all the school system is well organized, and last the kid's are given extra time on work.