Answer:
The letter combination that makes a rolling sound in Spanish is "rr".
Explanation:
One of the things that make the Spanish language distinctive is the sound of rolling that is made in words with double Rs.
Here are some examples of words with double Rs:
Carro (car), arrienda (leases), marrón (brown).
But using double Rs is not the only way to produce a rolling sound. Rolling sounds can also be made when the R is the first letter of a word.
Examples of words that start with an R (and have a rolling sound):
Roto (broken), rueda (wheel), risa (laugh).
