What do you call it when you stitch felt on to fabric?

What does bts stand for? what is the importance of bts? who first started it?

Escribe un adjetivo a cada sustantivomelodiosas - claro - mole.stos - oscura - espaciosos - bulliciosas - tranquilo - acogedora - día - noche - músicas - ruidos - casa - pueblo - pisos - ciudades

Order these space notes in the bass clef from highest space to the lowest space