So teacher I just finished my test on the grammar, I think is little bit hard. Some stuff that I don't really know what is that mean and like some time they gave you a question, and when you starting to answer the question you feel like they try to trick you and make you confuse too. For EX: They want you to  click on the sentence that uses hyphens appropriately.
 ( 1. Officer Boomer was knocked to the ground by the recoil. His still smoking gun went spinning down the alley. ( 2. Officer Boomer was knocked to the ground by the recoil. His still-smoking gun went spinning down the alley.) I need some help on that.