Relative clauses give more information without starting a new sentence. For example:

"He couldn't drive. I was surprised he couldn't drive", can be combined to create the more fluent sentence "he couldn't drive, which surprised me". Our English relative clauses video lesson gives more examples of the purpose of relative clauses. This video is part of our collection of English video recorded lessons with qualified teachers. The library of lessons is available to anyone who subscribes to ESO's media package. The videos are short so you can squeeze a quick lesson in whenever you have time, and you are welcome to go back and watch the same video as many times as you need to, for example if you are revising for an exam.