[Xuande]

Well, my book says that it means either an action in progress or that it connects a past event to the present which is the part I don't understand. I know that something like benkyoushiteimasu means studying right now but when you add imasu to the end of certain te-form verbs it kind of changes how they are used. I guess an example might be something like "yaseru," which is to lost weight, but when you use it like "yaseteimasu," it means to be thin. Its kind of hard to explain but I hope that explanation helps.