If you want to know more, here is an article about a tweak that will do it. http://www.idownloadblog.com/2012/10/06/ipad-mouse/. Though the article is old, the tweak it described still works on iOS 8.4. You can also connect a keyboard and mouse at the same time, and the iPad will display a cursor for the mouse.
Have + been + verb + -ing. The _______ is used for an event that has been completed before the present moment in time. Simple past. When a progressive tense is used in the independent clause, the dependent clause typically uses the _______ tense. Simple past. Read the quotation below and complete the instruction that follows.
The verb of the main clause is in the future tense with  will  (or sometimes another modal). The verb of the conditional clause is in the simple present tense. Occasionally, the open conditional statement describes one potential state of reality or circumstance which is dependent on another.