The r and rr are distinct. The "rr" is trilled, like the previous poster said. Non-native speakers will have trouble with this and it will take years, if ever, to aquire this. The "r" in rosa sounds like "perro" to many non-natives, but they're not the same.

Put your tounge on the roof of your mouth and breathe out. your tounge should touch the back of your front teeth

Hola, lo primero que tienes que hacer es colocar la punta de tu lengua en tu papila incisiva (la parte del paladar que esta justo detrás de tus dientes). Ahora has que tu lengua vibre como si fuera un helicóptero. Estaría bien que hicieras un poco de gimnasia facial, sacando tu lengua y moviéndola de arriba a abajo y de izquierda a derecha. Practícalo todos los días. Saludos. Hi. The first, you put the tip of yout tongue in your incisive papilla. Now, you have that your tongue vibrate how if this be a helicopter. You to do a little of facial gym too; you put out yout tongue and move it from top to bottom and from left to right. You practiced it everyday. See you.