When 라 comes after a verb, it makes an imperaive sentence. And it may sounds like a command. 가라 meanGO!!! Other examples: 먹어라 means EAT!!! 보라 means LOOK!!! 읽어라 means READ!!! Also, verb+주세요 makes imperative sentence, but this sounds more soft and smooth. I hope my answer can be helpful for you. ^-^