LL – Y

In Castilian Spanish, LL is considered a single letter, which is pronounced like an English "Y" at the start of a word. 

For example, you would pronounce llave (key) as "yah-beh" and pollo (chicken) as "poh-yoh".

The letters LL are pronounced Y

To remember this we use the following mnemonic:

The llama (LL) was playing with her yo-yos (LL=Y).