Report and vocabulary
After almost dying out in the 1970s, a kind of whistling language is now undergoing a revival.
Silbo Gomero, as it's known, has become a compulsory subject in one school in Spain's Canary Islands.
The whistling approximates the sounds of the Spanish language.
It can be heard from two miles away, and was used to communicate across valleys and ravines before the arrival of telephones.
- dying out
becoming less common until it finally stops existing
- undergoing a revival
becoming more popular again
required to be done
almost correctly copies
very narrow valleys