Tanyao
Tanyao is a yaku, consisting of tile groups using numbered tiles 2-8 of any of the three main suits. Conversely, this yaku must lack the terminal tiles (1 and 9) as well as any honor tiles. Among the yaku, this is one of the more easier to attain. In turn, it is also a cheap yaku. In addition, this yaku may be subject to rule variation of allowing or disallowing its count when opened.
Tile pattern
Winning tile: or
English reference
In English, this yaku is commonly referred as "all simples". In turn, all tile numbered as 2-8 are simple tiles.